Cook spaghetti according to package directions, except omit the cooking oil and only lightly salt the water. Drain well; keep warm.
Meanwhile, in a large skillet, heat oil over medium-high heat. Add sweet pepper and onion; cook for 3 to 5 minutes or until tender. Stir in pasta sauce and crumbled meat loaf. Heat through. Toss with hot cooked spaghetti. If desired, garnish with fresh basil leaves.