Mix butter, sugar and pretzels and pat into a 9x13" pan. Bake at 350° for 10 minutes. Cool.
Pour the boiling water over the Jell-O and stir to completely dissolve. Cool 25-30 minutes in the refrigerator - it should be cool enough to not melt the cream cheese, but not starting to gel yet. Place the sliced strawberries over the cream cheese filling. Slowly pour the cooled Jell-O over the strawberries. Chill until firm.