Where is my Registry Key

Are you perhaps referring to the Product Key?

If your system is still running, you can use Magic Jelly Bean Keyfinder to retrieve your product key.

http://www.magicaljellybean.com/keyfinder.shtml

If you are looking for the product key, while installing XP, you need to find the original package for the CD, or look on your case for the sticker that has the key.

The key is NOT stored on the XP installation CD.

Chas

If you are not seeking hte product key, then a particular key, value or DWord can be found in the registry hive.

The hive can be viewed and manipulated with RegEdit, which is part of the operating system. Incorrectly modifying the registry can destroy your system; thus, you have been warned....