I don't think you can, but you could get a direct play halo 2 from the torrent website if you wanted.
Uh, sorry to tell you, but that's illegal. To play halo Custom Edition you must have the original Halo and a product key (genuine)
no, halo is a Microsoft only product.
no
There is no way to get it without the Halo 3: ODST Campaign disk.
Not without hacking, no.
Yes, you can play firefight in Halo 3 ODST without Xbox live.
This is impossible to do.
It is impossible to play as a grunt in Halo: CE (aka. Halo 1) without modifying the game.
You can only play Halo 2 on the 360, and the first Halo is available for download on XBL marketplace, and has come down in price.
no
yes and no. You can play all the maps in the halo 3, but you have to download the rest.
Any one can play Halo Reach, as long as the person has a Xbox (Microsoft product). Halo Reach can not be played on a PS3. Also, you need a game card so you can play online. But, if you do not have a game card you can still play regular