I just wrote a long post and got bumped, so here it is short and sweet.
It can get very very hot and humid, be sure your hotel has a pool, make sure it is clean. Stay on the Canada side, the hotels in NY are dirty and the town is basically a slum.
Do the Maid of the Mist ride, and the walking tours of the American Falls, and the Canadian walking tours, don't worry, you will see the signs. And very expensive, about 10 miles from the falls on the Canada side is an awesome jet ski ride, that we had such an excellent time, it was worth every penny. Just ask anyone in the hotels or restaurants about it, they'll be able to tell you the name of it.
Planet Hollywood, a rip off, Hard Rock Cafe in NY, great food good price, great atmosphere. We also found a nice steak house on the NY side, about 10 miles south east, sorry I don't remember the name, we went there twice it was so nice.