Is their a hotel next door to the N.O. Arena and Superdome

Yes, the Hyatt is definitely out of commission. There are tons of places to stay that aren't far from the Arena, but nothing quite like the walking distance of what you had in mind. The Hyatt was the best for that.

That reminds me...yesterday at work, a drunk Ohio State fan wandered into our building and insisted to our receptionist that he needed a key to his room. Our building is a stand alone building, but we're one block behind a small hotel. She kept trying to tell him he was in the wrong building & he got very irate when she wouldn't call his wife in Ontario to confirm his story. I laughed my butt off when the cops hauled him away.