My family vacationed there during the summers for about 12 years and it's a great place. The thing I like about it is that there is NOT much to do. It is forced family time. No high rise hotels, no street full of bars, etc. Just a quiet and beautiful beach community. I do not recall seeing any marsh boats at all as that entire area is protected so you are likely out of luck there. There are only a few restaurants on the island itself. Here are a few things to do (not sure if they would interest you but here they are):
-Atlantic Beach (which is north of Emerald Isle) has a shopping mall and a few restaurants. May be fun to head up there if you have a rainy day.
-Head into Swansboro (go over the main bridge and take a left). There are some quaint shops and a few cafe's there. There is also a VERY good place to buy seafood (some of the best shrimp in the world) which is called Clyde's Seafood. It will be on your left in Swansboro. The shrimp boats dock there and you buy whatever they caught that trip. If you have kids, you can also ask some of the fishermen to give you a tour of the docks and boat. Kids love it. It is not a restaurant, but a place to buy seafood and cook it at home.
-If you're a golfer at all, there are a few nice courses close by (Star Hill comes to mind).
-Walk down to the Point which is at the southside of the island. The houses that they have built in that area are amazing and there is always good shell hunting down there. A lot of boats enter the Sound there and can be fun to watch as well.
-The beach itself is amazing. Rivals any beach in the US in my opinion.
Hope that helps a bit. While there is not a lot to do there, it sounds like you'll be on vacation. So you will be able to relax there without a problem. Have fun.
