Finally
AdAware latest version downloaded, installed and online updated. It found some CSS Stylesheet hijacking thingy... removed it!
Spybot Search & Destroy latest version downloaded, installed and run. Found something too but I can't remember exactly what it was... but I removed it. The update function in Spybot made it crash though.
Upgraded my Zone Alarm to the most current version.
Upgraded Windows with most current security updates.
Finally system seems normal. No more pop-ups on Greenguys or Tommys either