The registry is just plain evil. A bad idea that has gotten out of control, through use, abuse and misuse by developers, by Microsoft, by users, by third party tools and it's amazing to me that we still have to deal with it.
That being said, I would follow Mr. Anderton's advice first (
post #6 above) before attempting anything with the registry. But if you do have to venture into deleting stuff from the registry then make a backup of it first.