This is a silly question, but I'd like to say to the people who belittle Mozart, if you don't know Mozart's operas, you don't know Mozart. The Finale of The Magic Flute, Act 2 is like Beethoven's Ode to Joy in miniature, and I defy anyone to say it's inferior.
Even Beethoven, who was not a big Mozart fan, broke down and admitted that he liked The Magic Flute. Listen to his " Seven Variations On Welche Liebe Fuhlen From The Magic Flute."
On YouTube - the BBC's Genius of Mozart. Recommended esp., Part 2 - Passion for the Stage, about opera.