When I click start, click run, type in %temp%, a box of mostly temp files come up, when I try to delete them it won't let me. Right now I have about 42 files on there. Even when I try to delete one, the error box comes up and say I can't delete it.

Any suggestions will be helpful.

Thanks in advance.

Try it one at a time, any file that says it can't be deleted is probably being used.

Download CCleaner (CCleaner - Home) and run it... select anything you want to clear out. Its much easier :)

This reminds me of that old joke:

Man: "Doc, it hurts when I do this." (stretches a certain way)
Doc: "OK, don't do that anymore."

Are you sure you need to be fiddling with your temp files? Are you trying to solve some other real problem, or just fiddling?