Combine pretzels and 3 tsp sugar. Stir in butter. Press into ungreased 13 X 9 pan. Bake at 350 degrees for 10 minutes. Then cool.
Dissolve Jello in boiling water. Add pineapple and oranges. Chill for 30 minutes.
Beat cream cheese and sugar. Fold in whip topping. Spread over crust. Gently spoon Jello mixture over cream cheese. Refrigerate 2-4 hours.