Just so you know and you won't be embarrased if it isn't legit--
You will not be able to install SP1 without a **valid**
key that you will not be supplied with from this forum, but if you know somebody that knows somebody, then you may be in luck.
If this is not the case and it IS a legit copy, then call the MS tech line and they will help you with what you need.
Tech-Forums does not endorse or recommend piracy/warez. Support your local Monopoly and buy the product.