Use tools like Xbox 360 ISO Extractor or WX360 to unpack the files.
Alternatively, use ISO2GOD to convert the ISO into a GoD container, which allows the game to appear directly in the official Xbox dashboard. BulletStorm [Region Free][ISO]
To play this ISO on a modified Xbox 360, you typically need to convert it into a format the console can read from a hard drive: Use tools like Xbox 360 ISO Extractor or