I've only stayed in NY once, and I was at a hotel with a great location;
New York Hotels: Warwick New York Hotel Official Site. We were a few blocks from 5th Avenue, Central Park, Times Square, etc. It really was a wonderful location.
Check out this site:
New York City Tourism - New York City Vacation Reviews - New York City Vacations - TripAdvisor for tons of info about NYC. You can read about hotels, attractions, restaurants... everything. It's a great resource when planning a vacation.
I'd recommend seeing a show while there; I went around Christmas and saw the Rockettes at Radio City Music Hall. It wasn't something I'd have picked out (I was there on a business thing), but I'm glad I got to see it. There are a ton of shows on Broadway, and lots of great stuff off-Broadway too.
Enjoy your trip, whenever you get to go!