Halve potatoes; dont peel them. Cut kielbasa and corn into four-inch pieces. Pour enough water to cover ingredients into a large pot. Add bay leaves and crab seasoning. Bring to a boil. Add potatoes and kielbasa and boil for 20 minutes. Add corn and crab legs, if using; cook for 10 minutes more. Add shrimp and boil for 3 to 5 more minutes. Dont overcook the shrimp! Drain. At some Low Country gatherings, the table is covered with a thick mat of newspaper and the Boil is dumped onto it for all to share. Garnish with sliced lemons, and serve with melted butter for dipping, if desired. No matter what you use for a platter, serve with bread and beer.