Ok here's some random things the thread said to make sure and do
Make sure to walk through Central Park. Walk down 5th Ave. and check out the nice stores. We actually LOVE the Circle Line bus tours (I think that's the one.....) with the red double-decker buses. It's a great trip through the city and they teach you lots of little facts!!
The Staten Island ferry is free and you get a great view of the city from the water
If you want to see a show youc an buy your tickets on braodway they have a ticketboth whichyou can not miss in black and yellow. They open at noon I beleive. You can never be sure what they will have but they always have great shows for sale. There will be a line so I suggest you arrive early
If you like getting up early, it's fun to see the crowd that turns out in Rockefeller for the Today show and at Times Square for Good Morning America... The ticket booth someone else referenced is "TKTS" and is a GREAT way to see a show. (opens around noon) I've always gotten great tickets that way.
If you like cathedrals/architecture, I love walking into St. Patrick's Cathedral on 5th Ave. (right near Rockefeller). It's also an experience to browse Saks Fifth Ave. It's like a museum to me!
Checking out Canal St. downtown is always interesting, and you'll be right near some of the great Italian restaurants in Little Italy
(these are just bits from a diff thread...not my personal experiences...I've only seen the NYC/Manhattan stuff, been to some restraunts, and the Statue of Liberty)