Just download the file, that's all you need to do there.
NOTE: Microsoft stopped updating their backwards compatibility for original Xbox games years ago.
But as of the 2.0.16756.0 update, most apps do not require a Xbox Live Gold Subscription to access them, although the app may have its own subscription to be able to use it.
Microsoft released the Xbox 360 console on November 22, 2005, a whole year earlier than both the Sony Play Station 3 and Nintendo Wii.
Fans of World of Tanks will be able discover tournaments from the Xbox app, and will receive notifications when matches are ready, as well as automatic results and the ability to post them on activity feeds. In order to get these firmware updates for your Xbox, you normally would download them from Xbox Live. Like all game consoles, there are occasional updates to add new features such as social networking tools like Facebook, Twitter, etc or the ability to play different types of files.Xbox Live has two types of offerings, free and Gold Membership.The free version gets you free game demos, game add-ons, games on demand, arcade games, avatars, and voice/text chat.