Normally you should not need registry scan programs.
Most of them are a waste of time and a waste of money.
Many of these programs say they have found 1000 errors in your registry, just to trick you into buying their product.
It is rare that anything in your registry will cause major problems with windows.
If you are having problems then it is more likely to be a rogue problem or virus has been installed so try to uninstall that.
If all else fails a complete re-install of Windows will give you a nice brand new registry.