You could try a walk-up at Capt. Grille at YC if you don't want to commit to an ADR. Otherwise, the Fountain at Dolphin is a great suggestion. Good food, fun atmosphere. If you don't feel like walking, take the DHS boat one stop to Swan/Dolphin. You could also walk up to ESPN or Big River at BWI. I would just go early as the wait lists can build. You could also do the QS at BC and eat indoors or order room service!