Last year we went to Table Rock Lake. We stayed at a decent place right on the lake. It's priced decent. We rented a boat one day, hung out at the pool, went into Branson which is only about a 15 minute drive, and Silver Dollar City is right there close too.
We went to Fort Walton Beach, Florida for a few days two years ago and stayed at a hotel right on the beach. It had an inground pool and a little kids water park area at the hotel, which was nice. It was a little on the pricey side, but it was the first time my kids seen the ocean so it was worth it.