Preheat your oven to 450 degrees F. Bring the water and butter to a boil in a saucepan and add flour all at once, stirring until a smooth ball forms. Remove from the heat and let stand for 5 minutes.
Add the eggs, one at a time, beating well after each addition. Continue beating until the mixture becomes smooth and shiny. Next, transfer the dough to a resealable plastic bag, seal, and cut a small hole in one corner of the bag.
On an ungreased baking sheet, pipe eight 3 1/2 inch logs and bake for 10 minutes. Reduce oven temperature to 400 degrees F. and bake for an additional 15 to 20 minutes, or until the dough is a golden brown.
Remove from the oven, and transfer to a wire rack. Immediately put a slit into each eclair to allow steam to escape. Let cool and then carefully cut off tops. Then, set the tops aside and remove the soft dough from the inside with a fork.
To make the vanilla filling, beat 1 1/4 cups of milk, vanilla, and vanilla pudding mix on low speed in a mixing bowl for 2 minutes, or until thickened. Fold in the whipped topping and set aside.
To make the chocolate frosting, beat the remaining 1 1/2 cups of milk and chocolate pudding mix in a seperate mixing bowl for 2 minutes, or until thickened.
To prepare the eclairs, spoon the vanilla filling into each eclair and then replace the top. Finally, frost with chocolate topping and enjoy.