answer:Do you have a virus infection or registry problem, or is this a “what if” question? Windows does a pretty good job of fixing its own registry problems unless you start screwing around with a chainsaw like CCleaner. System restore works best after your system is screwed up by a botched install. That’s what I’ve used it for. It can rid you of some malware infections, but not all; it is no substitute for a good antivirus. It also uses a lot of disk space, so you want to keep the number of restore points at a minimum. It’s always good to manually set a restore point just before a software install, particularly if you’re installing something that’s bloated and/or requires multiple restarts and Internet updates. The chances of something blowing up are far greater then.