OK, I'm a legal owner of XP - however I bought it preinstalled on a premade computer. It came with no disk. Is it legal to install XP using another CD, since I'm not going to use my old computer again (half of the bits are missing now)? Also, I have a key from my old computer but it says it's invalid... how am I supposed to get a new key that works? Can I phone up Microsoft, tell them my problem, give them my old key and get a new working one?