Worth reading: The Three Musketeers. Its first sequel, Twenty Years After, was actually an improvement.
Everyone knows about Sherlock Holmes, but Arthur Conan Doyle's other book The Lost World is also pretty great. I haven't gotten around to the rest of the Professor Challenger series yet.
Shirley Jackson's The Haunting of Hill House was somehow a book I hadn't heard of (outside of it being the basis of a movie) and so it was a welcome surprise.
Luo Guanzhong's Three Kingdoms (aka Romance of the Three Kingdoms) is the best book of all time, of all time.
Frankenstein is really really good. Dracula is too, but I find Frankenstein the more satisfying experience (for some reason I often find these two together in collections, often accompanied by Dr. Jekyll and Mr Hyde).
Oh, and anyone who criticizes Tolkien is a leftist. This Are Fact.
.............
Not Worth Reading:
Unfortunately I found Alexander Dumas' other well-known book, The Count of Monte Cristo, kind of a slog.
I mentioned that for some reason I often see Frankenstein compiled with Dracula and Dr. Jekyll and Mr Hyde. Now, Jekyll is not bad reading, but.... thing is its kind of a proto M. Night Shyalaman movie where the whole story is leading up to a twist, but the thing is the "twist" is one of those that, thanks to pop cultural osmosis (and adaptations not even preserving it as a twist) everybody goes in knowing: That Rosebud gets stabbed by Sephiroth, who also killed Dumbledore, who was the sled. Because of that, reading it now is kind of a slog because you keep thinking that once that point comes up, the story "actually begins," but actually that's when the story ends.
(Okay, non-joke spoiler: The twist is that Jekyll is Hyde. Literally the whole story is a detective trying to figure out how they're connected and this is what he ultimately discovers, via Jekyll leaving a suicide note. I figured it wasn't worth revealing because I mean, everybody knows.... but just in case....)
Also on the "not worth reading" pile: Anne of Green Gables--I have no idea why I was forced to read this in school. Same goes for to Kill a Mockingbird. That latter I at least understand that it probably had some proto-SJW (I went to school in the 1990s) attitudes backing it. The thing is though, the trial of the black guy is actually just one part of the book... both it and Green Gables are basically "here's some random shit some kids got up to." Anne particularly pissed me off with how spineless she was, easily bowing down to everyone's whims no matter how unreasonable. Seriously some teacher starts crying because she read Ben-Hur and that makes Anne stop.
I'd say "fuck Anne" but you know some people back then probably wanted to.
On that note, I tried to read The Phantom of the Opera and absolutely could not stand it.