You can play it while signed into xbox live, but you cant play with other people through xbox live on oblivion.
oblivion uses aspect of xbox live but only for unlocking achievements and nothing else, you do not need xbox live and to be honest having it does nothing for the game itself
Elder Scrolls: Oblivion doesn't have any online multiplayer, so you don't connect to xbox live through the game. However, there is downloadable content on the xbox live marketplace, which you access through the Xbox Dashboard.
you play the game
No.
Unfortunatly, Oblivion is not multiplayer (at all) online, but you can download extras for the base game off the marketplace.
You can not buy the whole game on Xbox LIVE, but you can purchase the expansion pack: Shivering Isles.
You cant you have to download them from psn or xbox live
You can no longer play original Xbox games on Xbox Live.
What exactly is your question? Yes, Oblivion has an Xbox 360 version, if that was what you meant.
i dont think you can play it online but you can download additional content from xbox game market place(i think they are on offer at moment 4 like 85 points).
There is no way. PS3 users play on "PlayStation Network". XBox users play on "XBox Live".
No it is not necessary to have a High Definition T.V to play on Xbox Live.