Mix wafer crumbs and butter until blended; press onto bottom and up side of 9-inch pie plate.
Bake 5 to 8 min. or until golden brown. Cool completely. Meanwhile, make chocolate curls from 1/2 oz. chocolate. Refrigerate.
Microwave remaining 1-1/2 oz. chocolate and peanut butter in microwaveable bowl on HIGH 1 min.; stir until chocolate is completely melted and mixture is well blended.
Place bananas in crust; drizzle with melted chocolate.
Beat pudding mixes and milk in large bowl with whisk 2 min. Stir in 1 cup COOL WHIP.
Spread over bananas; top with remaining COOL WHIP.
Refrigerate 3 hours. Top with chocolate curls and nuts just before serving.