By Denny Dyroff, Entertainment Editor, The Times Winterthur Museum, Garden & Library (5105 Kennett Pike, Route 52, Wilmington, Delaware, 800-448-3883, http://www.winterthur.org) is  welcoming visitors back to its stunning house and galleries beginning October 1. In the Galleries, “Winterthur’s Lady of the House,” Ruth Wales du Pont explores her life as wife of Henry Francis du Pont,...