There are two programs that may be of benefit to you. One is 'RegCure', and the other is 'TUT', 'The Ultimate Trouble Shooter'. The use of both of them (together or not) needs to be thought about carefully.
'RegCure' 'cleans' the registry like is says it does. Whether you need that or not is open to debate. That 'TUT' program gives you the oportunity to get rid of some 'parasite' programs, ones that just don't do anything to your benefit. Or the programs that various manufacturers add to software for -their- use, not yours. Gotta be careful with that, but it certainly can be helpful.
Neither of them are free.
- 'Doc