You will want to use the following to scan your machine. Go through ALL of them to make sure that you have gotten all the junk out of your system:
Ad-Aware 6 build 181
Spybot Search and Destroy
CW Shredder
Hijackthis(more technical, so use with care)
Once these have been run, your system SHOULD be fairly clean. You can use msconfig and go through the startup tab to remove things you don't want before using the tools I mentioned.