That would be a great trip for your family. I would recommend Marriott's Aruba Surf Club with kids of that age as they would love the lazy river at the resort. There is plenty to do at the resort (pool, ocean, activities, etc.) but also some fun things to do if you want to venture off the resort. If you rent a car, there are other beaches on the island you can explore like Baby Beach. We also enjoyed a safari tour with ABC Tours (http://abc-aruba.com/)… your kids would really enjoy that. If your kids like animals, there is Philips Animal Garden (http://www.philipsanimalgarden.com/). They would likely have fun on DePalm Island for a day (http://www.depalmtours.com/de-palm-island). I think you would find plenty to do to fill your time there.