Sorry if this is long. I love this stuff.
My first question would be what type of classical music got you into it?
Orchestra, solo instrument, small ensembles, a movie scene, etc
I like to separate into classical periods, examples: Baroque (Bach, Vivaldi, Pachelbel), classical classical, (Mozart, Haydn) romantic (Beethoven, Brahms, many), impressionistic (Debussy, Ravel), nazi banned late romantic geniuses like Mahler. There are so many, especially when you get instrument specific. Then you discover South American, Cuban, Spanish etc music that wasn't well known and it blows your away.
How about Beethoven Symphony No. 8 in F Major, 2nd movement. It's easy on the ears, genius, has what would be considered comedy for it's time, melodic, short, and easy to dismantle without knowing theory.
But when all else fails just listen to a lot of Chopin.