How Do I Use Regedit & CCleaner To Backup/Clean My Registry?

I ran the latest version of CCleaner to scan my registry because I've been using this pc for quite a few years, and it found over 600 issues. I'd like to allow it to fix everything but before doing so I'd like to make a backup of my entire registry using Windows Xp's Regedit. I know I can also backup the registry with CCleaner prior to letting it fix what it finds. But I'd rather use Regedit because I heard it saves the registry better, or as a "whole" compared to CCleaner.

1. How can I backup my entire registry with Regedit in case of failure after using CCleaner?

2. How safe/reliable is CCleaner when it comes to cleaning/fixing the registry?

3. Doesn't Windows System Restore safe the entire registry? [meaning it would be useless to make a backup using Regedit]


Thank You

 

If I run CCleaner on a system that has lots of issues, I usually don't let it cleanup all. I do items in about batches of 50, use the computer for awhile to be sure nothing is broken then run again and do another batch of cleanups.
It takes longer but if something breaks, it is easier to restore 50 items than 600 and be back to square one with the cleaning.