Press the windows key (between the ctrl and alt key) and 'pause/break' at the same time.
That will show you either XP home or XP pro.
If that is a home system with a legitimate copy of XP then you can be 99.99% sure that is not a corp copy/install of XP. Besides, the only difference between the xp pro and xp corp is that you don't have to active the xp corp.
Another way to tell is at the startup screen. The screen with the little "light bar" scrolling under where it says Windows XP. Look at that screen and it will say home or pro. The color of the "light bar" is different too. If I remember right, it is blue for pro and I think it is orange or something for home.
Er, if its the FCK key then its an illegal corporate copy of windows xp and you should take it back immediatly.
And it wont accept your cd-key because its XP Corp and not XP Pro, also You can't put your own copy of XP onto another computer either, each copy can only be activated on one computer.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS