
Oooohh the options!!
I'd say:
1. Empire State on a clear day, don't bother with all the extra rides etc & walk back down
2. World Trade Centre & Century 21 for shopping - there are some really nice coffee shops around here for breakfast
3. Grand Central Train Station - some fab food courts that do lovely yummy cheesecake
4. Central Park - ice skate or take a horse drawn carriage around, magnificent!
5. Broadway show - there are quite a few discounted booths around Times Square where after a short queue you can pick up bargain tickets, I'd recommend Lion King.
6. Night out in the Meat Packing District, some amazing Thai restaurants, followed by a Comopolitan on one of the rooftop bars
7. Shopping - Fifth Avenue, Macys, Sephora, Saks. Barneys etc etc - take your credit cards!!
You will have an amazing time! :)