All you need to do is keep close eyes on www.ngemu.com for all your current/next generation emulation needs

As for X-Box, you'd be lucky mate :/ The only X-Box emulator that is showing any real progress can play 2 games, Turok and Halo, and neither of them play that well anyway.
There hasnt been much news on the X-Box emu scene lately anyway, so I'm afraid to say it will be along time before youre playing your XB titles on your PC, which is gonna have to be a powerful rig anyway to get them going.