like dyserq, i use a program called CCleaner.com .. it's really good, i recommend you download it and give it a try. You wouldn't believe how much rubbish you pick up.
Go to to C:\WINDOWS\, make sure 'Show Hidden Files and Folders' is enabled, and you should see some folders around the name of $nt$uninstall. Delete those.
Those folders are created when windows updates are installed, to allow you to uninstall updates. But why would you want to do that? Unless you use System Restore, maybe, but I have that disabled, as I find it does more harm than good.