What was the game demo? That could be the method of getting the worms into your machine.
Have you also got Spybot, Adaware, A-squared, Microsoft Anti-Spyware etc? Suggest you do scans with all of those, too - and oh, back up your data while you can in case you need to do a reinstall.
But I would have thought the various antimalware apps should find and sort out whatever's happened.