I got oblivion from games on demand, and i bought the dlc "shivering isles". so, yes.
Yes there are games similar to the DLC Quest that you can buy for the Xbox 360. You can find the similar games from game retailers such as game stop or online.
Depends on the game. Some xbox games are available for download through the xbox marketplace.
Yes, but you won't be able to install the game or any DLC to your console.
Xbox marketplace
No.
Dawnguard , the first DLC expansion, was officially released for the Xbox 360 on June 26th, 2012.
yes anything you get from xbox live will stick with your gamer tag but if you are wanting to buy it once for two xboxes that wont work
No.
yes it's on Xbox 360, you can buy it at your local game shop or on Xbox live
Zombie mode is after the PC PS3 and Xbox 360 games have completed and is not available for the PS2 or Nintendo Games. There are also 3 DLC for the PS3 or Xbox 360 that each include a new zombie map
dsd
Not really both playstation and xbox have its pros and cons. playstation has free online but its security is terrible. xbox you pay but its security is good. xbox also had a 2 week early dlc. Which xbox users get dlc's two weeks before playstation or other consoles. THIS IS ONLY ON PARTICIPATING GAMES.