This sounds like what happens when you hold the CTRL key down and start clicking on files to delete.  If you accidentally drag the mouse with the left click key down, it will duplicate all the files you have highlighted.  When You delete a batch of files using the CTRL and Left Click, make sure you release the Left Click key before you move the mouse to the next file.
When I try to delete pictures from my pictures folder, they reappear at the bottom of the folder. I am trying to clean up my pictures folder and everytime I delete a series of pictures, they reappear. I am running Window XP. How can I stop this reappearance of deleted pictures? Any help is greatly appreciated.
My Pictures Folder