Re: What to do in NY for a day or two?
I would say go to MoMA and if you have time also check out museum of Natural History.
It all depends on your interest, check websites for each museum to see whats on display right now and decide.
As for Broadway shows you can not go wrong with Lion King, Phantom both classics..but again do you like effects/substance...etc. Mary Poppins is supposed to be good as well.
I also know Rent is a great production as well as Mamma Mia. Hmm if you dont have time to plan in advance, in times sq..i think 43rd st...there is a huge booth in the center....ticket sumthing...and u can usually find discounts to some shows last minute.
Are you coming alone or with family/friends. You can also take a 1 1/2 - 3 hour cruise around manhattan, they even have brunch/dinner cruises with entertainment like on the Spirit of NY or NY Waterway. Also some very good comedy clubs that are fun to try. You can try the 'Comedy Cellar' at the Olive Tree Cafe in the village on 3rd n mcdougal. Also Laugh Lounge isn't bad, or more expensive would be Caroline's.
Also it may be touristy but the NY Aquarium is nice, so is the Bronx Zoo. You can also head over to NJ shore and hit the beaches, Point Pleasant isn't bad, and Belmar is nicer. Or drive into the Hamtons in long island......but too much for 1-2 days i guess.