I agree with Budapest
, about the Registry issues.
Unless you have a specific problem you're trying to correct, it's best to stay out of the Registry.
Registry cleaners mark entries as bad, depending on what the software creator thinks, is bad.
That's why no 2 cleaners will find all of the, same "problems".
Registry "problems" actually have very little effect, on the overall performance of the operating system.
As far as the cookies go, many sites require cookies, for the site to function properly.
If they're not tracking cookies, I wouldn't worry too much about them.
A program like Ad-Aware SE
, or Spybot S&D
, will remove tracking cookies, while leaving the "good" cookies.