There are no working boot discs for an unmodified Xbox 360 . The “King Kong” exploit was patched over a decade ago, and even it only booted Linux, not game backups.
Burn slowly. Boot bravely.
I can provide the exact modern steps or software utilities you need. Share public link Xbox 360 boot disk v2.4
Instead, what the modding community refers to as a "boot disk" typically falls into one of three categories: There are no working boot discs for an unmodified Xbox 360