I came across a similar problem with a pals pc an svchost process taking up all the processor power.I found this by opening the task manager and "end tasking" that svchost process. I did eventually solve it but I can't really remember how! (fat lot of help you are thinking). However it may be worth downloading and scanning with prevx CSI. It is free to use and you only pay if it finds a problem to solve. Unlike many of the AV / reg cleaner products that work on this basis and (supposedly) find hundreds of problems, it will only find problems that really exist. It has been a saviour for me a couple of times when all else failed.