Halo: Combat Evolved runs just fine on Windows XP.
Yes, its instores to buy; A Windows Live game.
halo 2
not legally
No. A few games from Microsoft, such as Halo 2, were modified to work on Windows XP because they did not actually use any Vista-specific features. In general, though, a game that says it requires Vista likely does, or at least will not work on XP without modification.
Of course. It wouldn't be a "Windows XP game" otherwise.
Halo 2 was designed and released as a 'Game for Windows' and only works on Windows Vista. It is said, however, that there are ways to get it to work on XP. Emulation is another possibility to use the xbox version of Halo 2 on any computer.
Only for Windows Vista, but you can use it on Windows XP, but that will stop Multiplayer from working.
you get one xp per win
yes you do, but there are hacks to make it work on XP
pinball
This is kind of a two-part answer, because I'm not sure about the question. 1 - Halo (the original) will work on XP, and should work on Vista. 2 - Halo 2 will only work on Vista.
Spartan ops seems to give more XP.. From experience