Martinique 26 is the very very closest, but then again, the pool and the gift shop are on the Trinidad North side, making Trinidad North 31 the closest to the pool complex. In other words, flip a coin!
"On paper," I'd say a 2nd floor room is going to be quieter and more private. You'll have no one above you potentially stomping on the floor. And, mathematically speaking, only half of the people in your building have the potential to be walking by your room, whereas in a first floor room you have the potential of 100% of the building's people walking past your room (everyone needs to walk past some of the first floor at some point, but only people staying in 2nd floor rooms have to walk along the 2nd floor).
But I can't imagine that makes a huge difference, in reality.