Have you tried Microsoft's Antispyware? It was free when I got it.
I also use Registry Mechanic from PC Tools which cleans my registry every time my PC starts up. If you are not an expert on fixing things in the registry directly, there are also other registry cleaners out there. In this day and age, it's beneficial to invest in antivirus, antispy and registry cleaning software to protect your computer as much as possible. Check
www.pcworld.com for the latest reviews and new about what's on the market or a freeware site like
www.freeware.com to get something for quick fixes until you can afford better. The antivirus software from Computer Associates is OK, but the experience I've had with that is it was free for 12 months only and when I wanted to get rid of it - I had problems getting it all off my PC, so now I opted for Norton.
To get help with your current registry problem, you should write down exactly what the error is, so that our computer experts can give you a better solution to your problem. Good Luck.
Keep us posted.