I totally agree with saga Lout.
I've been using computers isnce 1989 (not the same computer) and have only ever "cleaned" my registry about 4 times in the different PC's that I had been using at the time. I rarely recommend it, even CCleaner, but only if all else fails. Once you have done the clean, uninstall CCleaner, it seems to monitor your system and may cause uncertain results.
Edit - CCleaner also removes temp browser files and other things, make sure you uncheck the options that you don't want removed otherwise you may need to re-install your browser and have to reset your browser settings.