saute onion and garlic in butter and oil in large Dutch oven 1 minute. Stir in tomato paste. Cook 2 minutes, stirring constantly. Add 2 cups water, sugar, salt and pepper; stir well.
Place plum tomatoes in container of electric blender. Cover and process until pureed. Add to mixture in Dutch oven. Repeat procedure with whole tomatoes; add to mixture in Dutch oven. Simmer, uncovered, 2 hours, stirring occasionally.
Place chicken, ribs and sausage in roasting pan. Bake at 350° 35 to 45 minutes or until done. Add meat to sauce in Dutch oven, reserving pan juices. Pour 1/2 cup hot water into roasting pan with pan juices; stir well. Add to sauce and simmer, uncovered 1 hour. Add meatballs; simmer additional 1 hour.
Cook spaghetti according to package directions. Drain. Serve sauce over hot cooked spaghetti.