Cook the long-grain and wild rice according to the package directions; set aside. Melt the 2 tablespoons butter in a large skillet and saute the onion, pepper, and mushrooms for 5 minutes. Add the tomatoes and simmer until the vegetables are tender but not mushy. Cut the lobster meat into bite-size pieces. Melt the remaining ¼ cup butter in another skillet. Saute the lobster and shrimp for 2 minutes. Add the sherry, lemon juice, Worcestershire sauce, and salt and pepper to taste. Heat thoroughly. Arrange the rice on a heated serving platter. Top with the seafood, then the vegetable mixture. Garnish with the parsley.