Download and run this....

http://cleanup.stevengould.org/

Great little program for deleting temp files, temporary Internet files, history etc. And no spyware. Does what it says on the tin
I install this on all my customer's PC's now and run it
One guy's machine was practically unusable, ran just this program, deleted over 90,000 files and recovered nearly 3Gb of wasted space

I don't usually download programs for this kind of thing but this one is worth having...