Beside VLC, very few dvd players have access to all DVD movie options, namely menus, and mpv is not one of them, but I use mpv to access external subtitles with DVDs and have started to appreciate very much this very simple and light and yet very capable player, so that I would like to provide an answer on how mpv might be used as main DVD player in spite of (or maybe because) its very minimal GUI.
Using MPV to play DVD movies
dvd;mediaplayer;mpv
To start the main stream of a video DVD with mpv (instead of just simply drag & dropping the VIDEO_TS folder onto the mpv window) use the command :mpv dvd://(as specified by jasonwryan in a comment below), or even (replacing username with yours)mpv /media/username/*/VIDEO_TSSo, just use that with a keyboard shortcut or in a launcher; or a specific .desktop file can be created on the desktop or in ~/.local/share/applications like so (text editor like gedit is your choice):gedit ~/.local/share/applications/mpv_dvd.desktopwith[Desktop Entry]Categories=AudioVideo;Audio;Video;Player;TV;Exec=mpv dvd://Icon=/path/to/your/mpv_icon.pngMimeType=Name=Play DVD in mpv Media PlayerStartupNotify=trueTerminal=falseType=ApplicationEdit the icon path too: possibly use this,or this one.)The launcher button/icon can be put on the desktop, on the panel, or can be searched and executed from an applications launcher (Dash, Synapse, Kickoff, Wisker Menu, Slingshot etc)To access more than the main stream, one can go into the DVD's VIDEO_TS folder and look there for more, or you may try a different command (to be used as above in a shortkey or launcher): mpv /dev/sr0which will play and seek through all included streams including menus as if in a single file. But the results of that may vary from good to very bad (for some reason the image is awful sometimes with this command).The mpv gui is very minimalistic, but it includes two buttons to cycle audio streams and subtitles, and they work for DVDs too. The next/previous buttons will change the chapters inside the video stream (not the different streams/titles)It has many possible shortkeys. The defaults ones are described as follows:NAME       mpv - a movie playerSYNOPSIS       mpv [options] [file|URL|-]       mpv [options] --playlist=PLAYLIST       mpv [options] files       mpv [options] {group of files and options}       mpv [bd]://[title][/device] [options]       mpv dvd://[title|[start_title]-end_title][/device] [options]       mpv dvdnav://[longest|menu|title][/device] [options]       mpv vcd://[/device]       mpv tv://[channel][/input_id] [options]       mpv radio://[channel|frequency][/capture] [options]       mpv pvr:// [options]       mpv dvb://[card_number@]channel [options]       mpv mf://[filemask|@listfile] [-mf options] [options]       mpv cdda://track[-endtrack][:speed][/device] [options]       mpv [file|mms[t]|http|httpproxy|rt[s]p|ftp|udp|smb]://[user:pass@]URL[:port] [options]       mpv edl://[edl specification as in edl-mpv.rst]DESCRIPTION       mpv is a movie player based on MPlayer and mplayer2. It supports a wide       variety of video file formats, audio and  video  codecs,  and  subtitle       types.  Special  input  URL  types  are  available to read input from a       variety of sources other than disk  files.  Depending  on  platform,  a       variety of different video and audio output methods are supported.       Usage  examples  to  get you started quickly can be found at the end of       this man page.INTERACTIVE CONTROL       mpv has a fully configurable, command-driven control layer which allows       you  to  control  mpv using keyboard, mouse, joystick or remote control       (with LIRC). See the --input- options for ways to customize it.   Keyboard Control       LEFT and RIGHT              Seek backward/forward 10 seconds. Shift+arrow does  a  1  second              exact seek (see --hr-seek).       UP and DOWN              Seek  forward/backward  1  minute.  Shift+arrow  does a 5 second              exact seek (see --hr-seek).       PGUP and PGDWN              Seek forward/backward 10 minutes.       [ and ]              Decrease/increase current playback speed by 10%.       { and }              Halve/double current playback speed.       BACKSPACE              Reset playback speed to normal.       < and >              Go backward/forward in the playlist.       ENTER  Go forward in the playlist, even over the end.       p / SPACE              Pause (pressing again unpauses).       .      Step forward. Pressing once will pause movie, every  consecutive              press will play one frame and then go into pause mode again.       ,      Step backward. Pressing once will pause movie, every consecutive              press will play one frame in reverse and then go into pause mode              again.       q / ESC              Stop playing and quit.       Q      Like  q,  but  store  the current playback position. Playing the              same file later will resume at  the  old  playback  position  if              possible.       U      Stop playing (and quit if --idle is not used).       + and -              Adjust audio delay by +/- 0.1 seconds.       / and *              Decrease/increase volume.       9 and 0              Decrease/increase volume.       ( and )              Adjust audio balance in favor of left/right channel.       m      Mute sound.       _      Cycle through the available video tracks.       #      Cycle through the available audio tracks.       TAB (MPEG-TS and libavformat only)              Cycle through the available programs.       f      Toggle fullscreen (see also --fs).       T      Toggle stay-on-top (see also --ontop).       w and e              Decrease/increase pan-and-scan range.       o      Toggle  OSD  states: none / seek / seek + timer / seek + timer +              total time.       d      Toggle frame  dropping  states:  none  /  skip  display  /  skip              decoding (see --framedrop).       v      Toggle subtitle visibility.       j and J              Cycle through the available subtitles.       F      Toggle displaying forced subtitles.       x and z              Adjust subtitle delay by +/- 0.1 seconds.       V      Toggle   subtitle   VSFilter   aspect  compatibility  mode.  See              --ass-vsfilter-aspect-compat for more info.       r and t              Move subtitles up/down.       s      Take a screenshot.       S      Take  a  screenshot,  without  subtitles.  (Whether  this  works              depends on VO driver support.)       I      Show filename on the OSD.       P      Show  progression  bar,  elapsed  time and total duration on the              OSD.       ! and @              Seek to the beginning of  the  previous/next  chapter.  In  most              cases,  previous  will  actually  go  to  the beginning of the              current chapter; see --chapter-seek-threshold.       D (--vo=vdpau, --vf=yadif only)              Activate/deactivate deinterlacer.       A      Cycle through the available DVD angles.       c      Change YUV colorspace.       (The following keys are valid only  when  using  a  video  output  that       supports  the  corresponding  adjustment,  or  the  software  equalizer       (--vf=eq).)       1 and 2              Adjust contrast.       3 and 4              Adjust brightness.       5 and 6              Adjust gamma.       7 and 8              Adjust saturation.       (The following keys are valid only on OSX.)       command + 0              Resize movie window to half its original size.       command + 1              Resize movie window to its original size.       command + 2              Resize movie window to double its original size.       command + f              Toggle fullscreen (see also --fs).       command + [ and command + ]              Set movie window alpha.       (The following keys are valid if you have a  keyboard  with  multimedia       keys.)       PAUSE  Pause.       STOP   Stop playing and quit.       PREVIOUS and NEXT              Seek backward/forward 1 minute.       (The following keys are only valid if you compiled with TV or DVB input       support.)       h and k              Select previous/next channel.       n      Change norm.       u      Change channel list.   Mouse Control       button 3 and button 4              Seek backward/forward 1 minute.       button 5 and button 6              Decrease/increase volume.The ones that I find especially helpful are:r and t              Move subtitles up/down.j and J              Cycle through the available subtitles. #      Cycle through the available audio tracks.  w and e              Decrease/increase pan-and-scan range.Those can be customized ingedit ~/.config/mpv/input.confBy default, it is:# mpv keybindings## Location of user-defined bindings: ~/.config/mpv/input.conf## Lines starting with # are comments. Use SHARP to assign the # key.# Copy this file and uncomment and edit the bindings you want to change.## List of commands and further details: DOCS/man/input.rst# List of special keys: --input-keylist# Keybindings testing mode: mpv --input-test --force-window --idle## Use 'ignore' to unbind a key fully (e.g. 'ctrl+a ignore').## Strings need to be quoted and escaped:#   KEY show-text This is a single backslash: \\ and a quote: \ !## You can use modifier-key combinations like Shift+Left or Ctrl+Alt+x with# the modifiers Shift, Ctrl, Alt and Meta (may not work on the terminal).## The default keybindings are hardcoded into the mpv binary.# You can disable them completely with: --no-input-default-bindings# Developer note:# On compilation, this file is baked into the mpv binary, and all lines are# uncommented (unless '#' is followed by a space) - thus this file defines the# default key bindings.# If this is enabled, treat all the following bindings as default.#default-bindings start#MOUSE_BTN0 ignore                      # don't do anything#MOUSE_BTN0_DBL cycle fullscreen        # toggle fullscreen on/off#MOUSE_BTN2 cycle pause                 # toggle pause on/off#MOUSE_BTN3 seek 10#MOUSE_BTN4 seek -10#MOUSE_BTN5 add volume -2#MOUSE_BTN6 add volume 2# Mouse wheels, touchpad or other input devices that have axes# if the input devices supports precise scrolling it will also scale the# numeric value accordingly#AXIS_UP    seek 10#AXIS_DOWN  seek -10#AXIS_LEFT  seek 5#AXIS_RIGHT seek -5## Seek units are in seconds, but note that these are limited by keyframes#RIGHT seek  5#LEFT  seek -5#UP    seek  60#DOWN  seek -60# Do smaller, always exact (non-keyframe-limited), seeks with shift.# Don't show them on the OSD (no-osd).#Shift+RIGHT no-osd seek  1 exact#Shift+LEFT  no-osd seek -1 exact#Shift+UP    no-osd seek  5 exact#Shift+DOWN  no-osd seek -5 exact# Skip to previous/next subtitle (subject to some restrictions; see manpage)#Ctrl+LEFT   no-osd sub-seek -1#Ctrl+RIGHT  no-osd sub-seek  1#PGUP add chapter 1                     # skip to next chapter#PGDWN add chapter -1                   # skip to previous chapter#Shift+PGUP seek 600#Shift+PGDWN seek -600#[ multiply speed 0.9091                # scale playback speed#] multiply speed 1.1#{ multiply speed 0.5#} multiply speed 2.0#BS set speed 1.0                       # reset speed to normal#q quit#Q quit-watch-later#q {encode} quit 4#ESC set fullscreen no#ESC {encode} quit 4#p cycle pause                          # toggle pause/playback mode#. frame-step                           # advance one frame and pause#, frame-back-step                      # go back by one frame and pause#SPACE cycle pause#> playlist-next                        # skip to next file#ENTER playlist-next                    # skip to next file#< playlist-prev                        # skip to previous file#O no-osd cycle_values osd-level 3 1    # cycle through OSD mode#o show-progress#P show-progress#I show-text ${filename}              # display filename in osd#z add sub-delay -0.1                   # subtract 100 ms delay from subs#x add sub-delay +0.1                   # add#ctrl++ add audio-delay 0.100           # this changes audio/video sync#ctrl+- add audio-delay -0.100#9 add volume -2#/ add volume -2#0 add volume 2#* add volume 2#m cycle mute#1 add contrast -1#2 add contrast 1#3 add brightness -1#4 add brightness 1#5 add gamma -1#6 add gamma 1#7 add saturation -1#8 add saturation 1# toggle deinterlacer (automatically inserts or removes required filter)#d cycle deinterlace#r add sub-pos -1                       # move subtitles up#t add sub-pos +1                       #                down#v cycle sub-visibility# stretch SSA/ASS subtitles with anamorphic videos to match historical#V cycle ass-vsfilter-aspect-compat# switch between applying no style overrides to SSA/ASS subtitles, and# overriding them almost completely with the normal subtitle style#u cycle-values ass-style-override force no#j cycle sub                            # cycle through subtitles#J cycle sub down                       # ...backwards#Ctrl+A cycle audio                      # switch audio streams#_ cycle video#T cycle ontop                          # toggle video window ontop of other windows#f cycle fullscreen                     # toggle fullscreen#s screenshot                           # take a screenshot#S screenshot video                     # ...without subtitles#Ctrl+s screenshot window               # ...with subtitles and OSD, and scaled#Alt+s screenshot each-frame            # automatically screenshot every frame#w add panscan -0.1                     # zoom out with -panscan 0 -fs#e add panscan +0.1                     #      in#cycle video aspect ratios; -1 is the container aspect#A cycle-values video-aspect 16:9 4:3 2.35:1 -1#POWER quit#PLAY cycle pause#PAUSE cycle pause#PLAYPAUSE cycle pause#STOP quit#FORWARD seek 60#REWIND seek -60#NEXT playlist-next#PREV playlist-prev#VOLUME_UP add volume 2#VOLUME_DOWN add volume -2#MUTE cycle mute#CLOSE_WIN quit#CLOSE_WIN {encode} quit 4#E cycle edition                        # next edition#l ab_loop                              # Set/clear A-B loop points#L cycle-values loop inf no         # toggle infinite looping#ctrl+c quit 4# Apple Remote section#AR_PLAY cycle pause#AR_PLAY_HOLD quit#AR_CENTER cycle pause#AR_CENTER_HOLD quit#AR_NEXT seek 10#AR_NEXT_HOLD seek 120#AR_PREV seek -10#AR_PREV_HOLD seek -120#AR_MENU show-progress#AR_MENU_HOLD cycle mute#AR_VUP add volume 2#AR_VUP_HOLD add chapter 1#AR_VDOWN add volume -2#AR_VDOWN_HOLD add chapter -1# For tv://#h cycle tv-channel -1                  # previous channel#k cycle tv-channel +1                  # next channel## Legacy bindings (may or may not be removed in the future)##! add chapter -1                       # skip to previous chapter#@ add chapter 1                        #         next## Not assigned by default# (not an exhaustive list of unbound commands)## ? add sub-scale +0.1                  # increase subtitle font size# ? add sub-scale -0.1                  # decrease subtitle font size# ? sub-step -1                         # immediately display next subtitle# ? sub-step +1                         #                     previous# ? cycle-values window-scale 0.5 2 1   # switch between 1/2, 2x, unresized window size# ? cycle colormatrix# ? add audio-delay 0.100               # this changes audio/video sync# ? add audio-delay -0.100# ? cycle angle                         # switch DVD/Bluray angle# ? add balance -0.1                    # adjust audio balance in favor of left# ? add balance 0.1                     #                                  right# ? cycle sub-forced-only               # toggle DVD forced subs# ? cycle program                       # cycle transport stream programs# ? stop                                # stop playback (quit or enter idle mode)All needed explanations are inside this file.The default keybindings are hardcoded into the mpv binary. You can disable them completely with: --no-input-default-bindings, but it is more useful to use new more intuitive keys and mouse actions that can be added at the end of that file, like:Alt+a cycle-values video-aspect 16:9 4:3 2.35:1 -1Ctrl+a cycle audio                      # switch audio streamsCtrl+f cycle fullscreen        # toggle fullscreen on/offCtrl+s cycle sub                            # cycle through subtitlesMeta+UP add sub-pos -1                       # move subtitles upMeta+DOWN add sub-pos +1                       #                downMeta+Alt+s cycle sub-visibility             # show/hide subtitlesCtrl+z add panscan +0.1                    # zoom inCtrl+< add panscan -0.1                    # zoom outMOUSE_BTN0 ignore                      # don't do anythingMOUSE_BTN0_DBL cycle fullscreen        # toggle fullscreen on/offMOUSE_BTN2 cycle pause                 # toggle pause on/offMOUSE_BTN3 add volume 2                # increase volume with mouse wheelMOUSE_BTN4 add volume -2               # decrease volume with mouse wheel#MOUSE_BTN5 add volume -2#MOUSE_BTN6 add volume 2MOUSE_BTN1 cycle-values video-aspect 16:9 4:3 2.35:1 -1Ctrl+RIGHT seek  60Ctrl+LEFT  seek -60UP    add volume 2DOWN  add volume -2As already mentioned, mpv is the best way to add external subtitles to DVDs.