Visit Times Square if you must, but don't stay too long - it's a huge tourist trap and overrated. And definitely don't eat at the restaurants there! Waste of money.

For bars, I highly recommend Top of the Strand; its on the rooftop of a hotel with a ridiculously awesome view of the Empire State building. For something really cool, go to PDT (Please Don't Tell). It has a secret entrance so just find out more on Google.

Foodwise, there are too many places to name! But check out the Spotted Pig, great burger there. Katz Deli is a bit of a tourist trap but the sandwiches there are just amazing.

Chelsea Market is a must; there are a ton of things there to check out and lots of great eats.

If you are into culture, go to the cloisters in upper Manhattan; takes a lil bit of effort to get there, but the place is beautiful.