I think what's important is the uncompressed size (about 90 megs for kof2003), not the zipped one; please correct me if I'm wrong. If you already have Linux on your XBox, why not just use XMame (mame's port to *nix systems)? This would not eliminate the memory issue, but at least it would be a soulution to the performance one. I must admit this is offtipic.