try starting Windows in safe mode - when you turn the coputer on, repeatedly hit F8. Instead of Windows starting normally, it will show you a very basic menu with options like "start windows in safe mode", "start windows in safe mode with command prompt", etc... choose "start Windows in safe mode" - this will prevent many non-critical services starting, and often stops virus or spyware processes starting too.

Once you're logged in in safe mode, run your virus scans. Also download and run Spybot - Search and destroy.