1. Crush the Lemon Oreo cookies in a food processor or blender until you have fine crumbs. Reserve 1 cup of the crumbs for topping the lasagna at the end. Place the remaining crumbs in a medium mixing bowl. Add the melted butter and mix well. Press the butter and crumb mixture into the bottom of a 9x12 inch pan; refrigerate while you move on to the next steps.
2. In a large mixing bowl, with an electric mixer on medium speed beat together the cream cheese, half of the Cool Whip (reserve the remaining half to top the lasagna at the end), the powdered sugar, and the juice of one of the lemons. Spread the mixture evenly over the chilled crust; refrigerate while you move on to the next steps.
3. In a large mixing bowl, whisk together the milk and both instant pudding mixes until thickened. Spread the mixture evenly over the cream cheese layer of the lasagna; refrigerate for 1 hour.
4. Spread the remaining half of the Cool Whip over the pudding layer, then sprinkle with the reserved cup of Lemon Oreo crumbs.
5. Slice the remaining lemon into wedges and use to garnish the lemon lasagna. Slice the lasagna and serve chilled