Generally, you don't need to do much registry cleaning to keep Windows running happily.
It is a bit of a myth about registry cleaning speeding up Windows. I only use CCleaner
to clean the registry after uninstalling software, since it always finds a few issues
after that. If you are concerned about cleaning out traces of your usage of the system,
CCleaner is very good for that. It is a good housekeeping tool, worth keeping. Cheers.
Spexx.