I've pretty much decided I'm gonna go for a mac, with OS X Leopard on it. BUT run Windows XP 32 from inside Leopard itself as if I'm running any normal application. So I can run it like a Mac and a PC at the same time. If it's possible, I'd use a dual screen set-up with the spaces (I know Dual Screen is possible, but not sure how it'll work with spaces) and have both running side by side... Which also, is apparently very easy to set up and there is actual software you can do it with.

Thanks for the help guys!