Well the strategy you employ to fight off a virus depends on the type of infection itself. It's a tedious process and explaining it in a post is even more tedious and probably that's why none have replied to you!
But here's what you can do that probably should work. It actually does for minor infections!
Download an anti-spyware like Ad-Aware, Windows Defender or Ewido etc. Install it and boot your PC in safe mode. Run the anti-spyware you installed and do a thorough scan. This should remove the infection!
If the anti-spywares are unable to remove the infection try free anti-viruses like AVG, Avast! etc.
If the virus doesn't let you install the anti-spyware properly try online scan services like TrendMicro's HouseCall, Ewido's OnlineScan or Panda's ActiveScan etc. Online Scanners will require you to install their plugin/activex control and would normally run on IE only.
Hope this helps!
