Are you a DBag or just an idiot. This may seem like a trivial question but it isn't, I need to know which box to pidgeon hole you in.
Have you checked your hard drive for bad sectors ? Is it simply old and tired ?? Most system laggs are hard drive related - as the mechanical components start to wear out the spin up time starts to blow out, seek times become longer and the whole thing slows down.
. I've always had luck with both CCleaner and Advanced System Care. What one doesn't catch/correct the other will. I've never had an issue with either program messing up the registry. They both create back ups. I'd stay far far away from Norton. It's known to bog down and bury itself within the OS. Use Avast 5 Home edition (Free). Also use Malwarebytes and SuperAntiSpyware (both free).
sam3971, It's different stroke for different folks. On the contrary for me, Windows7Manager has been the best utility for me. TuneUp 2010 and System Mechanic Pro 9.5 messed up my PC big time. For System Mechanic, I had to reinstall my OS