Southport is a cool town to spend a few hours in. Eat at the Trolley Stop, and get some serious hot dog action. Theres a reason why people stand in line for 20 minutes for a hot dog... LOL Then catch the ferry over to Ft Fisher/Kure Beach.
Ft Fisher is the place to go if you want to run the beach. We passed thru from Sunset Beach north thru Southport and the ferry to Ft Fisher Memorial Day weekend. It was bring an idiot to town, get 4 more in free day in Kure Beach and Carolina Beach. Was quite a change of pace of being on a nearly desolate island in Sunset. They had amusement park rides at the Boardwalk in Carolina Beach. Dont know if they are there all season. If youre on the boardwalk, you have to stand in line for Britt's Donuts. Take some back to OI, and be crowned king of your domain for all eternity (they really are that good)...
As said, the aquarium is good to kill a few hours at Fort Fisher.
Wilmington has the USS North Carolina battleship museum. Give the boy a history lesson and look/listen for the ghosts on board the ship.
If you want to stay local to Ocean Isle, hit one of the fishing piers in OI or Sunset Beach. We were watching 3-4 ft wingspan rays cruising along the pier at Sunset looking for food. There is also fishing on the sound side. Ocean Isle has better shells, Sunset Beach has the walk to Bird Island and the Kindred Spirit mailbox. Google that if youre interested. Its a 2 mile each way walk down a desolate beach. Both towns have surf chairs (think land cruiser of wheel chairs for the beach) that they will loan you for free. Allows those not fortunate with good legs or stamina to enjoy the beach and water.
Giggling Mackerel on Ocean Isle will be crowded. Theres a putt putt place on Ocean Isle, right before the beach. Expect it and the ice cream place there to be packed too. The Jamaican place on the road between OI and Sunset was packed when we drove by. It sits about 200 yards off that road on a side street.
Calabash is the place to be for food.... The Seafood Hut is top notch (although not much to look at from the outside). Dockside is another great seafood place, and its right on the river. Gravy is a place for southern comfort food and artery cloggin. Calabash Creamery has awesome ice cream. Theres a deli/sandwich shop across the street from the creamery that is a great lunch or breakfast stop. Stay away from the Boundary House, high dollar tourist trap restaraunt. The place across the street from the boundary is good, little pricey.
There are good non-seafood restaraunts in Sunset Beach, right off of hwy 179. The italian place behind food lion is good. Theres also a Fibber McGhee's Pub, although we didnt eat there.
Callahans at Calabash will consume a couple hours of walkin around looking at neat stuff. There are several really good thrift/consignment/resale shops where you can get good stuff cheap. Heck, even the Ace Hardware store in Calabash is top notch.
If you do decide to go to Myrtle, theres a place called Everything Under the Sun (google that too). They have a mix of everything inside, and one guy sells new World Wide Sportsman, Bimini Bay, and other famous maker fishing wicking/high spf shirts for 12-15.00 a piece. There are a couple of good putt putt courses in North Myrtle right on Hwy 17. one has a Twin Beech airplane with spinning propeller, and a huey heli with spinning rotors. We didnt go far into Myrtle, so cant comment too much on other places there. We did catch a live radio spot on 94.9 the Surf, and got a $30.00 gift certificate to Duffy Street seafood place. Was really good food. The station is local to North Myrtle, and plays a lot of beach music, local music, etc.