How To Back-Up a X-BOX Game
Backing Games Up with Evolution X
Before you can do this, you must be able to FTP to your xbox and have the EvolutionX dashboard installed.
1. Getting the Files
Connect to your Xbox with your PC using EvolutionX. In this tutorial I will be using the game "Halo".
After you connect, go into the "D" drive. This is the dvd rom which has your game and the files you want in it. You should make sure you have enouph space on your PC HDD before you copy.

Also, remember to make a folder in FlashFXP and double click to go inside it. You wouldn't want to mix all those files...
Anyways, select all the gamefiles and folders on the right side of FlashFXP. Just click and drag them into the left hand side and they should start to copy. Depending on the game, this could take a while (not too long though).
When all the files are finished being copied over, you can quit FlashFXP and shutdown your xbox. You have to create an iso image of the game next.
2. Making the ISO image
There are a couple programs you can use to make the iso. One is "Isomaker 2.0", which is probably the best, and then there's "Xiso". I will be using Xiso because it is more common, but you should know that it is full of glitches and you are likely to get a bad iso image with the larger game files.
With that in thought, start up Xiso.

Click on Tools , then on Make a xISO . Select the folder that you copied your game to and hit OK. Then select the destination of the iso file and hit ok.

The iso may take a while to create, so sit back and play your xbox. When it finishes, your iso should be ready to burn.
(Credits xboxtutorials)