Give this software a try, it is called Spy Sweeper, you can use the trail version and make sure you allow the software to do a live update before scanning:
http://downloads-zdnet.com.com/3000-2144-10200144.html
Install the software first, then disable system restore, reboot the system and the scan it for pest and Trojan, I'm perrty sure it will get rid of your that problem.
cheers