ComputerWiz, welcome. The Windows product key is tied to your system, not to the install disc. Since it sounds like you plan to use WGA and not try to circumvent it, there should be no problem provided that you install the same flavor of XP as the license key is designed for. For example, if the license is for XP Home OEM, you would not be able to install XP Pro Retail and use the key you have to activate it.

I suspect if the license key and XP flavor don't match that it will let you know. So, I would suggest that you activate it as soon as possible to be certain that you will be able to continue using XP.

Well, I don't know the answer to that one. I would actually be curious to know myself. Is it the activation that decides whether the flavor of XP is Retail or OEM; or, is it the installer? This is why I suggested that you activate ASAP. If it's not going to work, you want to know right away.

EDIT: quick update. A google search suggests that the OEM key will NOT work with the Retail disc. :-(

Jon is right, an OEM key will not work with a retail install. There is Possibly a way around this though. Does your Dell have a recovery partition? Or are the XP install files in a folder on your C: drive? If they are then you can use Nlite to make an install cd. If that doesn't work for you then their are two solutions. First, if your family member calls Dell they can get them to send a new OEM CD. The other alternative is you can go to a local mom and pop computer store where they build custom PCs and such. They usually have a collection of those Dell CDs reminiscent of the collection of old AOL CDs people used to have. If all else fails.......is it illegal to share and OEM CD with others if you don't share the KEY?