Sorry it wouldn't happen. It might have some of the games available on the xbox arcade....but that's a maybe.
And since users aren't allowed to develop their own apps, that means there will never even be a chance of a emulator being made.
GBA is owned by nintendo a competitor to Microsoft.
PSone is owned by playstation a competitor to Micorosoft.
It'll just never happen.
As for the rest, Doom, Quake, i don't know about those. I think Doom is on the Xbox so there might be a chance it'll make it over to the zune.