thanks for all the information. The Hampton Inn looks nice, it is about the same price as the Grand Hyatt, what would be best? Thanks for the info on apartments2book, I am sure we would be happiest in an apartment so will look at them. Should we do free Staten Island Ferry trip or Circle Line tour? Cheers kate

I have stayed at the Grand Hyatt and found the Hampton rooms larger and nicer. We had 2 queen size beds in our room so the 3 of us were in 1 room. If you are a member of AAA that would help with the room rate.
At the Hampton it is very easy to catch the subway to the History Museum. Walking distance to Central Park. Across the street from the Hampton we found Ray's pizza and an Asian restaurant.
We liked this area as it was not as congested as mid Manhattan and around Grand Central Station.
Whatever you decide it will be a great time to visit.

You could spend all day at the Museum of Natural History. Also, consider the Planetarium which is adjacent to the museum - if the weather is nasty, you could have a great day indoors - the museum has a wonderful xmas tree decorated with origami. As you get closer to your trip, check online for special exhibits at all the museums. Once in awhile, those special exhibits require timed tickets which you can buy online. In any event, you can check in advance to see if anything special would appeal to your family. Don't forget Air and Space museum in DC. They usually have a wonderful IMAX film that all of would enjoy.