I have found that after causing any deletions to the registry, such as using Crap Cleaner or RegScrub XP after removing a program, that System Restore WILL NOT USUALLY WORK. The moral is that you should create a restore point after using such programs. I have posted this warning on another forum, and several people have tried this out by using these programs and then trying System restore. In NO WAY would I suggest not using such programs, I find them very useful. Just be aware that System Restore will probably not work unless you create a new restore point.
It appears to be a matter of luck as to when Windows makes it's own restore points. What I am pointing out is that I have found that such restore points do not work after deleting items from the registry with these programs. Therefore it is wise to immediately create a new restore point yourself.
Thanks for the tip. I myself tried out what you said and the same thing happened to me i.e. system restore didn't work after running cr*p cleaner. I have always thought that XP's system restore was a hit or miss affair and your post backs up that assumption. Cheers.