Which is the best registry cleaner?

Does this have to do with your computer freezing per your other thread?

Registry cleaners are, in general, a scam designed to exploit non-technical users' fears about their computer not working properly.

... which is really too bad. I think its a valid need.

The only ones I've seen that worked well - and this was quite a while ago - were ones that tracked what you installed and all the changes made. Then when you wanted to "clean", it made sure that now non-existent applications had all their changes reversed or removed. And actually, I know there are applications that do just this.

The problem is its difficult to clean unless you know any specific entry is "dirty", and no all registry keys are such that they can be easily traced back to whatever application installed them.