Line two 13x9-inch pans with foil; set aside. In a mixing bowl, combine 3/4 cup peanut butter and 1 1/2 cups milk till smooth. Slowly beat in chocolate pudding mix till blended; fold in 1 cup whipped topping. Pour into one prepared pan; freeze till firm. Repeat with vanilla pudding and remaining peanut butter, milk and whipped topping. Pour into second pan; freeze till firm.
Break or cut crackers into squares. Cut frozen pudding mixture into 32 squares, about 2 1/2-inches x 2 1/4-inches, place each square between two crackers. Wrap in plastic wrap. Freeze overnight. Makes 32 sandwiches.