My mate is having a problem with photos on his PC. He said he put them in his "My Pictures" folder as normal. Later he decided he wanted to remove them. He highlighted the files, right clicked and then selected delete. When it said "are you sure you want to remove these to the recycle bin?" he clicked yes. He then got a box saying "The files have been deleted" as normal. However, when he went back into the "My Pictures" folder, he found that not only were they still there, they had multiplied! He went through the process a few more times, and had to stop when he reached 90+ copies of each pic! I don't know why he asked me coz I know nout, hopefully someone here can help!
Try starting the computer in safe mode (tap the F8 key as it's starting up) select the safe mode option and try deleting from there.
Download an antivirus (AVG or Avast) and get the most recent updates and run that. Also anti spyware.
I did this only last week gazza, but instead of the 90 copies that your friend had I ended up with over 200. I've been trying to re-create how I made such a mess but unhelpfully for you it's now working fine.
You can end up with copies if you have a lot to delete and are in too much of a hurry because you inadvertantly press the Copy instead of Delete. Not a huge problem but a pain all the same.