(just coincidental that I was the 13th poster, BTW)
Hmm. Betrayal in Antara. Don't have it myself, so hard to tell. Released in 1997, that means Compatibility Mode for Win 95 ought to do it in XP, else you're outta luck...
The hardest games to get running in XP are the ones made between 1996 and 2000. They were all striving to get the most performance they could out of Win 95/98, broke a lot of the unwritten Win 32 API rules, and so... luck of the dice roll with these ones, really.
Edit: just checked on www.ntcompatible.com.
Looks like it will run in XP but that you need to have your screen resolution set to 640 x 480 and also use a PC slowdown progam like Turbo or else the game crashes often in combat.