Sounds more like a resource problem. Something must be sucking up too much CPU resources.
Right click on the blue toolbar at the bottom or your screen and from that select Task Manager.
Click on 'Processes' and look for a big number in there (like more than 50,000).
IF there is something big running twice (other than svchost) do a Google search on it.
Just enter the name of the process (something.exe) in Google and see what you find. SOmetimes your browser will hang and not close properly and while it appears there is only one open, there is another running...big resource loss there.
IF nothing is running twice, start googling from the biggest number to the smallest to see if you have a virus in there.