After 5 hours of trying, I got Civ4 to run on my PC!

[kozzer]

I tried everything that has been posted here, but none of it worked. I'm running on WinXP MCE SP2 with a Radeon 9550.

I just took a stab into the dark, and set up a new user account in Windows. I immediately launched the game and it worked! And it runs very well!

Not at all sure why this would fix the issue, but I'm not arguing. I just wish I had discovered this hours ago, because I gotta go to bed...