1In medium bowl, pour boiling water on gelatin; stir until gelatin is dissolved. Stir in yogurt until melted and smooth. Cover; refrigerate about 1 hour 30 minutes or until thickened but not set.
2Meanwhile, heat oven to 350°F. Place cereal and pretzels in food-storage plastic bag; crush with rolling pin to make 1 1/2 cups. In small bowl, stir crushed cereal mixture and melted butter until well mixed. Press mixture firmly in bottom of ungreased 9-inch glass pie plate. Bake about 10 minutes or until crust is light golden brown. Set aside to cool.
3Beat gelatin mixture with electric mixer on high speed 7 to 8 minutes or until doubled in volume. Fold in sliced strawberries; pour over crust. Cover; refrigerate at least 1 hour or until firm.
4To serve, cut pie into wedges. Top with whipped topping and strawberry halves. Refrigerate any remaining pie.