Place peaches and lemon juice in a blender or food processor. Cover and process until smooth., In a microwave-safe bowl, sprinkle gelatin over peach nectar; let stand 1 minute. Microwave on high for 30-40 seconds. Stir and let stand 1 minute or until gelatin is completely dissolved. Let stand 5 minutes. Stir in pureed peach mixture. Pour into eight 8-oz. glass dessert dishes. Refrigerate until set, at least 3 hours., In a small saucepan, sprinkle gelatin over milk; let stand 1 minute. Heat and stir over low heat until gelatin is completely dissolved. Stir in cream, sugar, lemon zest, salt and vanilla. Pour over peach gelatin layers. Refrigerate until set, at least 2 hours. If desired, garnish with peach slices and mint leaves.