For SCUBA diving, I recommend staying at The Hamanasi Dive Resort (www.hamanasi.com
) They are a top notch dive resort with an excellent staff that mostly does everything for you, like hauling your gear to the boat and rinsing it off after the dives. I don't recall there being any shore diving, but you can go out on kayaks. All the diving was by boat and if you can luck out with the weather, go diving when a high pressure system is in the area as that flattens out the water and it won't be as choppy plus it cuts your time on the boat by almost half. The reefs are amazing and visibility is 80+ feet typically.
The food is very good, but I thought the breakfasts could have been improved. The beverages (milk, juices) could have been colder.
I also recommend going on the jungle hike to the falls, but it can be a rigorous lot of exercise... hot and humid. I've heard the Jaguar Preserve can be hit or miss with being able to spot the animals. I opted not to go.
Hopkins is a small town with a little nightlife. Not a lot to choose from.