Should work... you might run into a few driver problems on the first few start-ups, but it should fix itself. There's always safe mode, Windows repair disk, Hiren's, etc should something go wrong where it won't boot.
Windows will probably have you reactivate because it flips out with new motherboards (they see everything). If MS asks what happened, the answer is "lightning fried my mobo and I was forced to upgrade." They haven't the last few times I've upgraded, but it's happened before.