Beethoven, Leonore #3, Egmont, Consecration of the House
Berlioz, Roman Carnival
Mozart, Marriage of Figaro, Don Giovanni, Magic Flute
Lalo, Le Roi d'Ys
Tchaikovsky, Capriccio Italien (and others!)
Shostakovich, Festive Overture
I've long been a fan of the concert overture, and often when I set up a formal listening session, I'll program first an overture followed by a concerto and then a symphony, often selecting the three items according to some related theme. Below are a couple of my favorite overtures that Talk Classical folks should visit if they do not yet know them:
Peter Boyer "Celebration Overture"
Samuel Barber "Overture to The School for Scandal"
Leonard Bernstein "Overture to Candide"
Ralph Vaughn Williams "Overture to The Wasps"
Beethoven "Egmont Overture"
Brahms "Academic Festival Overture" and "Tragic Overture"
Mendelssohn "The Hebrides Overture"
Havergal Brian "Comedy Overture: The Tinker's Wedding"
Arnold Bax "Festival Overture"
Uuno Klami "Nummisuutarit-alkusoitto" ("The Cobblers on the Heath, Overture")
Étienne Nicolas Méhul "Overture: La Chasse du Jeune Henri"
Dmitri Shostakovich "Festive Overture"
Of course there are many more. But part of the joy of our hobby is exploring musical byways. So ... go on and explore.
My no. 1 at the moment: Die Schöpfung by Haydn.
Giulio Cesare and Solomon overtures by Handel
Grand overture by Giuliani (stretching the definition a little)
Romeo and Juliet overture by Tchaikovsky
La Clemenza di Tito and Die Zauberflöte by Mozart
Die Freischütz by Weber
Will have to think some more about others I enjoy....