^+1 The problem you are running into with the run command is that the first file it finds that can't be deleted it stops at that file and won't delete anymore. CCleaner is your best bet, It's here and it's free
Also try out (Startup programs) under Tools in CCleaner. You will be surprised what is running. Also use the Reg Cleaner if you havent cleaned the Registry lately.
Why do I have an error deleting a temp file?
I get it. I closed the program and it was deleted.
Steven Gould's Cleanup utility will eliminate this concern for you.