SALZBURG, Austria, July 31 - If only Mozart could see his hometown now. His letters are full of disdain for Salzburg, which he saw as hopelessly narrow-minded and parochial. As he wrote to his father, he felt constantly undervalued by his employer here, the Archbishop Colloredo, whom he despised "to the point of madness." He finally ended his service to the court on "that happy day" in 1781 and described to his father being booted out the door by Colloredo's deputy, with what is surely the most famous such kick in music history.