check to see if the manufacturer of your 3d card (mine was an asus GeForce) has issued an XP certified driver. I know most of them have, but it is a real headache to install a new OS and then finding out that your card manufacturer doesn't have the driver ready, and you won't be able to play any of the latest game since they need the customized OpenGL driver that came with the card; and the one microsoft supplies, depending on the card, may or may not work. Otherwise XP is more stable than all the other 9x OS.
BTW, about that scar. It also appears in another screenshot (namely #3) as I mentioned in another thread. Maybe it's part of the storyline???