I don't know if Bobby flay can beat an Iron Chef. He's good and all, but the Iron Chefs are some of the best in the world. bobby flay has his own show partly because he's charismatic, and not just on his cooking ability. I think his range may be a bit limited, especially with the asian based ingredients that seem to happen all the time.
Ming Tsai probably would still get his ass kicked, and I don't really think Emeril would do too well against the iron chefs. Emeril is not abotu subtlety, which I think is what wins a lot of iron chef battles.
Iron Chef Morimoto is amazing. His japanese fusion techniques are incredible to watch. Also, their ability to stick their fingers in hot oil for a taste is too crazy.