To make the crust, use a food processor to crush the vanilla wafers. Then, stir in the melted butter and press firmly into a pie pan. Freeze until the filling is ready.
To make the filling, whisk together the instant pudding and milk. Then whisk in the softened cream cheese, lime juice, zest, and sugar.
Pour the filling into the prepared pie crust and refrigerate or freeze overnight (see note). Garnish with lime wedges and whipped cream before serving.
You can refrigerate or freeze this pie before serving. If you refrigerate, it will thicken/harden but will remain soft, like a very soft cheesecake. If you freeze, it will harden more, like an ice cream cake.