The best shopping is right at the pier where the shuttle docks. There are dozens of shops within a two-block area.
We took the Island Tour (not including the sea). This stops at many of the same points. Hell truly is a tourist trap, although my two kids loved mailing all their friends postcards from Hell. There's a real post office in Hell. The turtle farm was nothing special unless you'll like holding sea turtles (they're cute).
Good luck!