Hawaii, no where can make you feel like. There are many kind of water sport and activities for your children as much as you want. Take a look at Hawaiian Vacation Kailua to choose the house rental that fits for your family members.
Kauai Travel Blog has details of Kauai local activity or attractive places to go such as seeing native foliage and fauna, native birds, riding a horse, swimming, surfing.
This picture is one of beach house looking from balcony through the sea. You can choose many houses from Kauai Vacation Rentals. You can also rental some car in this page. The houses are available for choosing by numbers of sleeps, location. By the way you can choose some condo too.