Grape Salad with Yogurt Dressing

2 cups Green and Red California grapes, halved and seeded, if necessary
1 Orange, peeled and cut into chunks
1 Banana, peeled and sliced
1/3 cup Celery, sliced
1/3 cup Orange or Lemon-flavored Yogurt
1/4 cup Waltnuts, broken
Lettuce cups (optional)

Combine all fruits and celery; gently stir in yogurt and nuts. Refrigerate at least one hour.