No
No.
playstation 2 is better
You can not play xbox games on a playstation 2
No. While Xbox 360 and PlayStation 2 games both utilize DVDs as storage mediums, the formatting and architectures for which the games are designed to run are are completely different.
No, the Halo games are only made for Xbox/Xbox 360
Yes.
The systems are not completely compatible. Just because you have a Playstation 2 game it may or may not, just as an XBox game may or may not, play on your Xbox 360.
Games are designed for a specific console, so no, they won't.
I'm pretty sure you can't do that
No, its a totally different format.
The Final Fantasy games can be played on PlayStation, PlayStation 2, PlayStation 3, and PSP
The Xbox is not designed to play PlayStation 2 games. A serious modification would be required to accomplish this feat, however, with the use of an Emulator one could play a PlayStation 1 game on an Xbox, but the legality of this is very questionable.