If you want to keep your computer running as it should then you will want to be sure to look into keeping your registry in good shape. When it comes to choosing the best windows registry repair utility you want to take a few things into consideration.
I am using Eusing Registry Cleanner which is here:
I have used these before:
Spybot S&D (Search and destroy)
and some other less important ones.
For registry defrag, I use Free Registry defrag which I think it is made by Registry Clean Expert. Freezes sometime during operation (normal, but annoying) but works ok.
ccleaner works fine for me...