Ok, so you’re pretty sure your registry is what’s causing your computer to run slow. What next?

First, perform a system restore. A computer with Windows 2000/XP/Vista should allow you to open the following utility form:

Start- All Problems- Accessories- System Tools- Backup (System Restore in Vista)

Once it’s running, choose a restore point. If you are aware of the date the problems started, pick a restore point before that date, and then follow prompts.

This should fix your registry, though problems could remain. You may need to go back even further, or there might not be any restore points available if they were never created

At this point, you need to edit the registry and get rid of the errors yourself, BUT BEWARE. This can be a difficult process, and if you don’t know what you’re doing, a registry cleaner is probably the best choice

More information on How to Repair Corrupt Registry Files