Can XBMC play Blu-Ray disks without other steps (e.g. manually decrypting it - if I buy a Blu-ray movie, can it be played out of the box)? 
Can XBMC play Blu-Ray disks?
xbmc;blu ray
I don't know a lot about XBMC, but it looks like the bluray comes as a plugin:http://lifehacker.com/5621471/how-to-enable-blu+ray-playback-in-xbmc