Combine low fat ice cream, peaches, amaretto and vanilla in a freezer safe container; stir well. Freeze until firm. Place thawed raspberries, sugar, and liqueur in a blender, and process until smooth. Press the raspberry mixture through a sieve, reserving puree; discard seeds. Cover and chill. Spoon 2 teaspoons raspberry puree into each of 8 parfait glasses or champagne flutes. Top each with about 1.5 tablespoons fresh raspberries and quarter cup ice-cream mixture. Repeat layers, ending with 2 teaspoons raspberry puree. Garnish with peach slices.