Bring water to a boil in a small saucepan; add gelatin, and cook, stirring constantly, 2 minutes or until gelatin dissolves. Chill 15 minutes. Gently stir in cold ginger ale. Cover and chill 1 hour or until consistency of unbeaten egg white. Gently stir 15 seconds. Stir in 1 cup grapes, oranges, and pineapple.
Pour into a lightly oiled 6-cup mold. Cover and chill until firm or up to 3 days ahead. Unmold salad onto a lettuce-lined serving plate. Garnish, if desired. Serve immediately.