I had AVG Antivirus&Antispyware on my computer. Last year when I was running the Antispyware the computer shutdown by itself? From then until now I have experienced a slow computer, occasional shutting down - both at varying rates. When it happened last year, over a month, trying to update the virus descriptions etc., eventually the computer shut down and would not start at all. I got assistance and got it into safe mode and eventually back to "just" working, and enough to do what I wanted to do, but as I said very slow and shut down of its own accord any time? Trying to work it out, just a novice by the way, it seemed to be something in the registry? I tried a couple of registry cleaners and found that the computer shut down at certain stages of it - it was like something knew it was coming and had a way of preventing being found? Recently I notice my computer being very slow, taking minutes to load things up and to switch between programs etc. I checked the Windows Task manager, which I have done over the last year to find many programs "Not Responding", and found that the CPU usage was at 100% a lot of the time. I googled it and found it might have been a registry issue which I have tried again to sort with registry cleaners/checkers etc for the past week, but now sending these questions in the hope someone can help me? I have read up some things on the discussion groups and want to make sure of what I am doing before doing anything with the registry? If the above descriptions sounds familiar to anyone can you please give me some advice.