any file under the windows/temp folder is safe to delete. Once in awhile windows will balk at one file. Just leave it for now. Also under C ocuments and Settings usernameLocal Settings are 2 folders. one is temp and the other is temporary internet files. You cant delete everything thats in these two folders also. Do it for each user account on the computer. You can also delete any file that has .log or .tmp at the end. I also delete the uninstall folders for windows updates and then remove the entries in add/remove programs once the computer is running fine.