I followed the complete readme on how to get Halo 2 working on WinXP.
But there are two problems:
1. When I choose to play Campaign, there opens a window which says me that I am not able to succeed because I'm not connected to Live.
2. After choosing the game difficulty, nothing happens. The screen keeps on being blue and stays. But also I can go back to choose the game difficulty again or further back. So the system doesnt hangs on, it simply does nothing after choosing the difficulty.
Greetz
Edit: Made a video with my cam, maybe it helps...
http://picasaweb.google.de/Jonnsta/