I would try either Myrtle Beach, SC or Wilmington, NC. Both are a lot of fun and do have plenty to do - even in the off season.http://www.cityofmyrtlebeach.com/http://www.cape-fear.nc.us/http://www.ci.wilmington.nc.us/
Atlanta, Savannah, are both pretty good places. Atlanta is much bigger so it would have much more variety.