Horry is probably done. He probably earned himself a spot in the HOF for his late game heroics contributing to rings for 3 different franchises, but at this point, I'd take Marshall over him for a last shot situation.
As for the Bulls, I still expect them to win the series. They are extremely talented since the trade, and it took a miraculous 2nd half from Allen, career nights from Rondo and Big Baby, and an off night for Derrick Rose for the Celts to squeeze out a victory. Now, going back to Chicago I expect the Bulls to jump on a shorthanded Celtic team.