How old are your kids, and when are you coming?
Things to do:
Beach (of course)
Battleship
Children's Museum
Cape Fear Museum
Jungle Rapids (mini golf, climbing wall, water park)
Shopping at Mayfaire or Lumina Station
Picking strawberries at Lewis Farms
Depending how long you are here - day trips to Myrtle Beach for Wonder Works and mini golf
Places to Eat:
Tower 7, K38, Las Olas (Mexican, all the same owners)
Bento Box or Nikki's (sushi)
Osteria Ciccheti (Italian)
Bridge Tender or South Beach (seafood)
Oceanic (best view, but I think the food is better at Bridge Tender or South Beach)
Nye's ice cream sandwiches (at Robert's Market) or Boombalatti's (homemade ice cream) or Kilwin's (homemade ice cream, but downtown on the river - nice stop if you go to the Battleship)
Port City Chop House or Portland Grille (steak)
Britt's doughnuts - Carolina Beach
This is all Wilmington. Topsail has a great beach, but I can't really help with restaurants.