Coarsely chop peanuts. Soften ice cream in carton in a microwave oven on medium power (50%) at 5-second intervals, 15 to 25 seconds.
Spread half the ice cream into crust, packing firmly. Sprinkle half the peanuts over ice cream. Drizzle about half the butterscotch topping over peanuts. Spread remaining ice cream onto pie, mounding in center. Top with remaining peanuts and butterscotch topping. Freeze until firm, at least 3 hours, or cover loosely and freeze up to 2 days.
To serve, let stand at room temperature about 10 minutes to soften before slicing into wedges.