In medium bowl, combine cracker crumbs, sugar, and melted butter. Press firmly on bottom and up sides of a 9-inch pie plate. Bake for 7 minutes and let cool completely.
In a medium bowl, add whipped topping and gently fold in condensed milk. Add limeade and zest and gently fold to combine. Do not let the mixture become soupy. Pour mixture into the pie crust and freeze overnight. Garnish with candied lime peels when ready to serve.