download [process explorer] and [rootkit revealer] from sysinternals.com

you shouldn't see any suspicious processes from tool 1. for diagnosis, you can copy and paste the list of processing running on your computer here.

for the second tool, you might need to run it in safe mode. to do that, reboot and press F8 and select Safe Mode.

for more information, refer to

http://research.microsoft.com/rootkit/

http://www.sysinternals.com/utilities/rootkitrevealer.html