I got that message that you spoke of and stupid me I hit yes. well it seemed to go after a lot of my games and such had to reload them to work. Could there be more unhappiness waiting for me?
Only about a 98% chance - sorry.
Scan your system with your anti-virus program, delete any infected files found, then update the anti-virus program and repeat.
Then visit the website for the anti-virus program you have, or go to http://securityresponse.symantec.com/ and look up the worms mentioned in the article: Kelvir.a and Kelvir.b and Sumon.a and Bropia (link describes this older worm - real nasty)
Here's the free Bropia removal tool from Symantec.
And the removal instructions from Symantec for: W32.Kelvir.E kelvir.a and Kelvir.B Couldn't find any for Sumon.a
The removal instructions all seem to have the same procedures, so once through should catch the above 3 worms.
You also might want to check out the IM Threat Center - this website has a list of IM threats and good info.
Good Luck,
RT