Place kiwi fruit and banana in a 15x10x1-inch baking pan. Place in freezer and freeze, uncovered, for 2 hours or until frozen**.
In a blender, combine grapes, yogurt, orange juice, honey, rum and about 1/3 of the frozen fruit. Cover and blend until almost smooth. Gradually add remaining fruit, blending after each addition until almost smooth. Add food coloring, if you like.
Pour into glasses and garnish with kiwifruit slices.
Rum may be omitted for a fruity, colorful, alcohol-free drink.
Once fruit is frozen, it may be transferred to a freezer container or storage bag for longer storage.
