I would try to check out the Museum of Modern Art when you have time. There's a cool Dali exhibit going on right now, and also it's just nice to be able to say you were a few inches away from stuff like Starry Night. (Doh, looks like Starry Night is out for a while, but there's lot of other great ones there too.)
When I went last, it was mainly to stuff my face and eat as much as possible
I definitely recommend finding yourself a Beard Papa
and if you're into Asian food at all, Momofuku
is a can't-miss.
There will be no shortage of things to do. Just open up Google Maps, center on where you're staying, and use either the points of interest map or hit the wikipedia option to show notable things around you.