FFVII would be awesome as well as Secret of Mana (spent so many hours playing this just to lvl up

)
But I'm happy that Sonic and track & field are going to be making it on XBA oh and not to mention paper boy.

(must buy some more points soon)
But I personally would love to see some of the older classics that got me into gaming in the first place on the VIC20 such as Jet Pack, Blitz, Space Invaders etc. So many happy memories.
I would even love to see a Marvel Vs Capcom type game make it on to the 360.
edit: just saw the post about the strike games and forgot how much fun I had with these as well. So many classics on the Mega Drive.