Need computer help, $20 on Stars

[gezuz]

I'm pissed right now, cuz I just formatted and got infected when a classmate told me to d/l a program. I dled Sketchup from sketchup.com the other night, and later that night I started getting popups at random in IE browser even though I use Mozilla. I've run Hijackthis and AVG, but the popups still hit me. My computer is also running slower now, but I can't figure out what's wrong.

Anyone that helps me fully get rid of this will get $20 on stars. I figure some people here are legit with computers and need stars money. I'll provide any necessary info.

thanks.