If you have 5 hours, you can go into Manhattan if your flight is on time. You'll have an hour or so to walk around midtown. Take the airtrain to the Long Island Railroad, which will send you express to midtown Manhattan. Total cost 10 - 12 dollars each way, depending on time of day, and total travel time each way is about 45 minutes. If your time window is tighter, stay at the airport. Take the free airtrain to Terminal 4 (main international terminal) where there are plenty of shops before security. This terminal is very interesting because many middle eastern and other exotic airlines use T4. You'll see some very interesting costumes! Have fun
If you have 5 hours, you can