he's legit. microcenter is a legit company. MS is a Ahole.
they did this a few year back when they lock every computer that they thought had a copy pirated windows. problem was...
they locked thousand of legit computers too. so they made up a story about a virus (msblast) causing the problems
the truth of the matter is ms can't tell if every computer isn't geniune or not. they will try though because they don't care. I suspect they will try locking them again in the near future
most company like dell sony, ibm and hp will use a corporate copy to install xp, yet put a different serial on the computer because they actually purchase that license on the side, yet it wouldn't be economical to manual install each serial to each computer, then activate them.
it's easier to use one corporate cd (image) with no activation required to install on all computers then slap a legit serial on the side
what kind of laptop is it? I can probably help you restore it