ad-aware 6.x then update it from within the settings to get the newest def files, make sure you AV program is up to date along with a small program called swat-it from
http://swatit.org/download.html
it is a trojan scanner that might help you as well use panicware.com popup stopper also and you should be fine
go through you control panl and remove software you arent sure of , if its legit when you try and use the actual program youll know and should be able to easily reinstall if it was legit to begin with. if however you got a dell or gateway or something pre-built this might not be a good idea cause all the stuff they bloat them with you might not know what its for but it could control a dell component etc etc etc,