In a medium saucepan combine marmalade, orange juice, cornstarch, margarine, and cardamom. Cook and stir until thickened and bubbly. Stir in fresh or frozen peaches and cherries. Cover and cook over medium heat for 10 to 12 minutes or until fruits are just tender, stirring once. Cool slightly.
To serve, spoon sauce into dessert dishes. Top each serving with a small spoonful of the frozen yogurt. Serves 5.