halo 3 does not have any cheats
no
None of the Halo's have any 'real' cheats, the only one is the lower your weapon one, which is just like Halo 3's.
no
No cheats
There are no cheat codes for Halo, only mods.
Halo 3 ODST is not for PC but Halo 1 and maybe Halo 2-3 are
no there are no "cheats" in halo, thought many glitches
Try www.cheatplanet.com and try there. There aren't any cheats in Halo 3 (not that i know of), but there are some really good glitches that you may like.
no there will not be halo 3 on the PC because Microsoft doesn't make PC's
There is no cheats.
No. Bungie stopped producing Halo games for Pc after Halo 2