|Were the pics on a USB connected drive, or on a memory card in a USB connnected card reader ?|
USB devices may not work correctly when they're connected to certain USB ports e.g. ports in a hub or on the front of a desktop case. If you have a desktop computer, you may have an IRQ sharing problem you need to fix, or your power supply may be starting to fail.
See response 3 in this:
Also - if you are using a USB extension cable, some of them have inadequate wiring and will not work properly with some USB devices.
Where did your girlfriend get the pics from?
E.g. If she got them from a place on the web that has illegally obtained downloads, there may have been malware embedded in the download(s).
"I drag them to recycle but it won't accept them."
A friend of mine discovered Windows XP has a built in upper limit that limits whether you can use drag and drop or not - that limit may still be there in Vista and Windows 7.
If what you drag and drop is over a certain huge size, you can't use drag and drop, but you can still RIGHT click, select DELETE - that will work
or RIGHT click, select CUT, go to where you want to place it, RIGHT click, select PASTE - that will work.
(In my friends case, she was trying to drag and drop one or more legally obtained movies or ebooks from one place to another.)