Drain syrup from pineapple, reserving juice.
Add water to make 2 cups. Heat to boiling
Add Jello, stir until solved.
Add Cold water. Chill till slightly thickened.
Fold in marshmallows, bananas and pineapple.
Pour into a 9x13" pan.
Chill til set.
Combine pudding with milk and mix well.
Fold pudding and cool whip together
Spread over Jello. Chill till set