I really like your question—wanting to try classics, but sensibly trying to avoid something so daunting that you’ll give up. I made a reply to a reply, but later realized that most of this thread, and I as well, were doing something I dislike: Mostly just throwing titles at you, but not giving any little tidbit that would help you choose.
So I’ll start over. (And I share your disdain for modern books.)
The Beautiful and Damned: It’s Fitzgerald’s Great Gatsby that’s the true classic, but this earlier book seems more energized to me. It’s the story of a young man—then, a young couple—in the 1910s-1920s who come from privileged backgrounds but are mostly waiting for a big inheritance, as their lives fall apart.
In Dubious Battle: I was surprised to find that I love Steinbeck, but, again, while Grapes of Wrath is the true classic, it’s huge, and to me bogs down intermittently. For some reason, I’m crazy about In Dubious Battle, and thought it the best book I’d read that year. It’s more or less about a down-and-out guy in the 1930s Depression who gets swept up on a small scale in a push for workers’ rights. In particular, I’m fascinated by the language, which is so simple, but so vivid. If you like nonfiction, Steinbeck’s Travels With Charley is a wonderful entertaining semi-memoir of a cross-country drive in the 1960s with his dog Charley.
Emma: I think Jane Austen is the finest English language novelist, ever. But although I love Pride and Prejudice, I’m starting to prefer Emma. Many people don’t like the character Emma, but I do.And I love all the collection of other people: the doddering hypochondriac father, the garrulously meandering neighbor, the young empty-headed friend. And I love the greater complexity of the plot.
Brave New World: This is, to me, one of the two foundational future dystopias in the English language (along with 1984).
Vanity Fair:This is admittedly long, but I eventually came to love it, and it’s now one of my top favorite books. The core story follows two girls, later into womanhood, who may be semi-friends but are totally different: The “bad” girl who is smart and conniving, and the “good” girl who is self-sacrificing and weepy. It’s a sprawling story interwoven with 19th century history, and very funny.