AVG Free 8.0 - Download and install it. Then go to safe mode and run it.
If that doesnt kill all the spyware, then go For
Spybot Search and Destroy - Again, install, update, and scan. This works well in normal or safe mode.
Lastly, if all hell has broken loose, and your getting nowhere fast, go for
Hijack This. Probably a last resort, but run this tool will stop everything from loading at startup. Once run, restart into safe mode/recovery and restore to about a week before you think it started acting up. Maybe more. Restore to that point.
And lastly, hire a professional if your not comfortable waging a small war with your PC.
Good luck,
Brad