Preheat oven to 375°. Make peaches: In a large bowl, combine peaches, sugar, lemon juice, cinnamon, ginger, and salt.  Make topping: In a medium bowl, combine flour, brown sugar, salt, and cinnamon. Pour in melted butter and stir until mixture resembles coarse crumbs.  Pour peaches and juices into a large baking dish. Sprinkle crumb topping evenly over peaches.  Bake until topping is golden and peaches are bubbling, 45 to 50 minutes. Serve warm with ice cream, if desired.