I know it is scary your first cruise, not knowing what to expect, but we learned to never book through the cruise lines. Much cheaper to just decide ahead what you want to do, get off the ship and either book from a vender by the dock, or just get a taxi. When we were on Grand Caymen, a taxi driver told us thank you for doing it this way, it is better for the local independants and the economy for the island if we don't use cruise ship exursions. You pay less, they get more, makes sense. If you are still nervous remember this, on these islands, their whole livelyhood depends on taking care of the cruise tourists, they want you back. Some islands, we calculated, have more than 10,000 tourists on any given day, and I have alwasy been impressed with how well they do it. Happy sailing