A small point, if you re-install using the Manufacturers key (i.e. the one currently reported by OA), it may not work with the Restore CD, you will have to use the key on the sticker.
This is because the key on the sticker matches the recovery CD. If it does work with the manufacturers key, then you can probably install this key on any machine, (not legally of course), as it is a Volume License key or similar. The manufacturers key may be from an entirely different media set however, and this would make it unusable with the recovery CD.
This can lead to some head scratching...