Preheat oven to 350. In a 3 quart saucepan, cook beef, onion and garlic over medium heat, stirring with a wooden spoon to break up meat, until cooked through, 8-10 minutes. Remove from heat. Stir in tomatoes, noodles, oregano, salt and pepper. Spoon into 1 1/2 quart casserole; sprinkle with cheese. Bake, covered, until heated through and cheese is melted, 15-20 minutes.