At the moment, I use "RegCure" here at work. There is a free version available at:
http://www.regcure.com/Seems to do pretty good, but its the full version. License will expire in 5 months, the boss will probably renew.
At home, I use whatever is most popular at the moment. There are so many out there now, it can be confusing to decide. Normaly I go to CNET (or similiar) and search for the most popular download and thats what I go with. If it doesnt do what I want, I move to the next. As always, caution should be applied when messin' with the registry .... if it ain't broke, don't fix it.
Your mileage may vary ....

FlySafe! Larry (Larrys4227)