The Xenia emulator reads .ISO files directly. However, it runs even better if you extract the ISO into an (unpacked folder structure). Use a tool called Xbox Image Browser to extract the ISO file directly into a standard folder containing the default.xex file. For Modified Xbox 360 Consoles (RGH/JTAG)
Web archiving projects sometimes hold ROM sets that have been optimized by the community. 2. How to Use Compressed ROMs (Emulation & Modding) xbox 360 roms highly compressed new