I <3 Halo:Reach - amazingly fun and best campaign + amazing Soundtrack
I <3 Halo 3:ODST - best soundtrack + Firefight + Coastal Highway and Mombassa Streets, amazingly unique campaign.
I <3 Halo 3 - best multiplayer levels + Forge + best Custom Games + soundtrack
I <3 Halo 2 - amazing huge fun campaign + soundtrack + Fun multiplayer
I <3 Halo: CE - started it all
Change you connection to Local, go nito camapign, hold down LB, RB, Click the left stick in, click the right stick in, and up on the D-pad. You now have pan-cam activated, Every invisible wall is now removed in theater mode.
Or, just start a campaign level, wait 10 seconds finish it, go into theater mode, watch the cutscene, but 2 seconds into it, rewind the film, and then hit the Y button.