You can walk out through the International Gateway and to the Beach Club where Beaches and Cream is located or you can take the Friendship ferry to the BC/YC. Their burgers and ice cream are fantastic. As for in the parks I agree that Pecos Bill's in the MK has good burgers. Two in park places I don't recommend for burgers are Rosie's All American Cafe in MGM(outside seating kind of across from the Beauty and the Beast and the Fantasmic theatre) and Restaurantosaurus in AK. The latter has McDonald's fries and chicken nuggets which are the same as you'd get at any McD's but the burgers are not McDonald's so don't expect a Big Mac there and the two times we've tried them they were big, but tough and tasteless.