Many a time you will want to edit your registry when you get your windows screwed and it refuses to boot up.
You know what changes should be made in the registry to fix the problem, but you don’t have any way to fix it. I had a similar problem and I used this tool to edit registry:
http://home.eunet.no/pnordahl/ntpasswd/main.html
This is a non-GUI bootable app. You should be familiar with the command-line and how it works before using it otherwise you may get into deeper problems.
This is another tool which I found while googling:
I hope this helps all you people who are thinking to reformat your computer because of registry errors.
Peace!