Sprinkle gelatin over half-and-half in a small saucepan; let stand 1 minute. Cook over low heat, stirring until gelatin dissolves. Remove from heat; cool slightly.
Combine yogurt and next 3 ingredients in a bowl. Stir in gelatin mixture.
Divide 1/2 of raspberries among 4 (6- ounce) ramekins or custard cups. Pour cream mixture over berries. Cover and chill 3 hours. Serve with remaining raspberries.