How To Deactivate Windows Xp

i want to just reinstall xp for a fairly old computer. well i want to reuse the key so i need to deactivate it first. i was just wondering how do i do that and anything to watch out for.

thanks

also just to add on this post. whenever i type in a new url in ie7 it automatically opens a new tab instead of going striaght to it. what settings needs to be changed to return it to the way it was.

i don't think there is such a thing as deactivating windows.
As long as the current license is not in use, you should just be able to install it on the computer and then activate it

You may have to make a call to the MS activation line. Usually that is painless and takes less than 5 minutes.