Ok this is my first post for the Month of May because my web server was down. And currently thinking of switching server but anyways. If you want to Enable or Disable your regedit simply follow this instructions.

1. Click on Start
2. Click on run
3. Type gpedit.msc then enter
4. Go to User configuration then Administrative Templates then System
5. Right click on Prevent Access to registry editing tools
6. Then you disable it if you want to use your regedit, otherwise enable to it to prevent users from editing your registry.

Note: If you want to edit your registry but its already disabled then you have to re-enable it first then disabling it again to work. Probably an Windows XP Bug.