Combine the ranch dressing, yogurt, and dillweed in a large bowl; stir well, and set dressing mixture aside.
Cook macaroni in boiling water for 5 minutes. Add peas, and cook an additional 3 minutes; drain well.
Add the macaroni mixture, bell peppers, and cheese cubes to dressing mixture, tossing to coat. Cover and chill. Stir before serving. Garnish with dillweed, if desired.