Finely crush the 24 Oreo cookies in a food processor. Add ¼ cup melted butter and mix until well combined. Press it into the bottom and up the sides of a 9" pie pan.
Bake the crust for 8-10 minutes. Cool completely, then place it in the freezer.
Scoop ½ gallon ice cream into a cake pan or bowl, chop and stir till smooth. Spread into the crumb crust. Cover and freeze for several hours.
When ready to serve, beat ½ cup whipping cream in a small bowl till soft peaks form. Beat in 2 tablespoon powdered sugar and ½ teaspoon vanilla.
Drizzle pie with ⅓ cup chocolate sauce, then top with whipped cream and additional cookie crumbs if desired.