1. To make Dressing: whisk together vinegar, oil, and garlic in small bowl, and season with salt and pepper, if desired.
2. To make Salad: cook orzo according to package directions; drain, rinse with cold water, and drain again.
3. Combine orzo with tomato, onion, feta, bell pepper, cranberries, walnuts, olives, and parsley in medium bowl. Add Dressing, and toss to combine. Serve at room temperature.