The Ritz-Carlton New York, Central Park

Without a question, the Ritz Carlton is one of the premium hotels in New York City. In contrast to some of the other big hotels in the area, however, the Ritz-Carltons's main entrance on Central Park South is rather inconspicuous and can easily be overlooked (our taxi driver drove right past the first time).
The rooms are very spacious and luxuriously equipped. The interiors are designed in a very tasteful, classic fashion and, of course, impeccably clean. The bathrooms are simply stunning (and larger than the bedrooms in some other hotels).
The staff are extremely helpful and friendly and make a point in making your stay as comfortable as possible. We arrived on a red-eye flight at about 5 am in the morning and technically would have had to wait until 3 pm for the official check-in time, but they let us check in right away.
There were some very minor glitches (not to detract from the 5-star rating, though): the bathtub stopper didn't work (we fixed it ourselves), and the tea water we had ordered from the room service was barely lukewarm when it arrived and hence unsuitable for actually preparing tea. But, oh well, these things can happen sometimes. Even the Ritz-Carlton is just run by humans ;-)
The price is in line with the typical "New York price factor", that is, anywhere else than New York City you can get the same quality hotel for a lot less. Notably, a nightly rate of $595 did not buy us a park view (we had a rather depressing view of the backside of the building with various grimy tubes and vents).
If you don't want a bad surprise (of which the hotel scene of New York City has plenty in store) then the Ritz-Carlton is a safe bet that won't disappoint.