Place 2/3 cup chocolates and milk in small microwave safe bowl. Microwave at MEDIUM (50%)30 to 45 seconds or just until melted and smooth when stirred; spread evenly on bottom of crumb crust. Cover; Refrigerate.
Beat cream cheese in medium bowl until smooth; gradually beat in sugar. Stir in peanut butter and whipped topping until blended; spoon evenly into crust over chocolate mixture. Cover; refrigerate 4 - 6 hours or until set.
Just before serving, place remaining 2/3 cup chocolates around edge of filling. Serve Cold; cover and refrigerate leftover pie. 8 servings.