Also, you should be fine using AirTrain and the subway getting into Manhattan, but I'd probably recommend taking a cab on the way back just because of time. With a 2pm show you'll be out probably close to 5 (depends on what you're seeing, but...) and it is a weekend, meaning the trains are not running as frequently, so you would be pushing it to get checked in and through security again. All cabs take plastic as well as cash now.
Experience live theater. Experience paintings. Experience books. Live, look and listen like artists! ~ imaginethis
LIVE THAT LESSON!!!!!!