Change $100 US at the airport, make sure they give you some (a lot, like $2kjmd in 500's, 100's and 50's) small bills - you will feel more at home with JMD in your pockets (and be sure to put most of it in a separate pocket). I've only had soup at Bigga's (my driver calls him "Biggs") and its very reasonable, and delicious. He has lids for soup, if you want to take some to the hotel with you.

Its a good idea to eat on your way to Negril; that way you can settle in without feeling desperately hungry.