In saucepan, combine fruits and enough water to cover.
Simmer gently, covered, 25 to 30 minutes, adding sugar for last 5 minutes of cooking.
Drain fruits, reserving syrup.
Add cold water to syrup to make 1 1/2 cups.
Dissolve gelatin in boiling water; stir in syrup mixture and sherry.
Chill till partially set.
Pit prunes; cut up all fruit.
Fold into gelatin.
Pour into 6-cup ring mold; chill till firm.
Unmold on leaf lettuce.
Garnish with frosted grapes, if desired.