Spread half of the crushed wafers in the bottom of a greased 8-in. square pan. Prepare pudding mix according to package directions; spoon hot pudding over crumbs. Slice one banana; place over pudding. Top with remaining crumbs. Chill for 1 hour. meanwhile, prepare gelatin according to package directions; chill for 30 minutes or until partially set. Pour over crumbs. Slice the remaining banana and place over gelatin. Spread whipped topping over all. Chill for 2 hours.