Yes I have it, but I also found a way to get it to work on a Windows XP machine as well.
There is a way to do the same for Shadowrun (but!!!) Shadow run has some very high requirements.

This is another reason I asked about everyone's video cards. This LAN is Doc's baby, and since he's been gone we've been doing everything we can to keep her fresh, that's what I try my hardest to do before we leave minot in another year or so.

So i'll will field test Halo 2 and let you know how it works in XP. By the way...Your video card must be better than an Nvidia 6600 and an ATI x700. I am testing it on an X1900 and ATI 9600 to see how drastic these minimum reqs are.

FAQ:

But I thought those games were made only for Vista...shouldn't I get vista to play them??
"Yes and no. Games for Windows is pretty much a MS marketing ploy, they want as many people to upgrade to vista as possible. Windows XP is going to stop selling Jan 08. So what better way to make about 80% of the PC market get vista...LIE, CHEAT, maybe even Steal!"

Is Vista worth it?
"In my opinion it's fine, for my home it makes the life of networking 10 times easier. Gaming wise all i've done really is UT2004, COD2, Rainbow Six Vegas (which i want to kill you all in), and a little of battlefield 2. Neither has really given me any problems. All except RB6 I kinda have to turn Compatability mode on to get it to start up faster...much faster. COD2 was the biggest offender taking 3+ mins to load upon startup. Now...10 to 15 seconds. A lot faster than XP did."

Let's face it, Direct X 10 is now, there is no going back to XP for DX10, I don't see how they can. Everything i've read states that it would change the OS all together and cause reverse engineering on a MASSIVE scale! Besides, a few XP nuances are gone..wouldn't you agree 13???

I say if you get a spare hard drive, try out Vista See what it does for your gaming platform. At the next LAN ask for me Mi6 300m!