In 2.03.532, every time I scan the registry, it comes up with a ton of "unused file extensions" like .txt, .doc, .html, .jpg, and tons more. I have files of all these types on my hard drive. On some of them if I let CCleaner "fix" the issues, the system no longer knows how to open them and I have to choose the default program again.
I'm using Vista Home Basic.