Hello dagzag,
I like using the free
Wise Registry Cleaner. It does a great job of keeping my registry clean.
WiseCleaner.com - Downloads
For a great free registry defragger, I like using
Auslogics Registry Defrag.
Auslogics - Download Auslogics Registry Defrag
If you need to repair the registry, then it is best to use the Vista
System Restore with a retore point dated before the problem.
Hope this helps,
Shawn