I can't add anything to the above recommendations, I just wanted to say have fun! I went to Manhattan in 2006 with my SIL and we had a blast. New Yorkers were SOOOOOOOOOOO nice to us! Everywhere we went, they were thanking us for coming to NY, giving us directions, recommendations, and tips. We'd get off the subway, climb up to street level and look around to get our bearings, and invariably someone would stop and ask if we needed help or were lost.
We did go on a foodie tour, I can't remember the name of it, but the guide took us through the meat-packing district and into a large food market where we got to sample a lot of different foods. My favorite has to be the sea-salted chocolates - they were AMAZING.