For humor and satire:
* The Adventures of Huckleberry Finn: Often considered his masterpiece, this novel offers a biting satire of 19th-century American society through the eyes of a runaway boy. It's full of witty dialogue, memorable characters, and powerful social commentary.
* A Connecticut Yankee in King Arthur's Court: This humorous and thought-provoking novel imagines a modern American transported back to medieval England, where he tries to modernize the kingdom with disastrous results.
For dark humor and social commentary:
* The Adventures of Tom Sawyer: While known for its lighter tone, this novel also explores themes of childhood innocence, racism, and the complexities of human nature.
* The Prince and the Pauper: This story about a pauper who switches places with the Prince of Wales is both entertaining and thought-provoking, exploring themes of class, identity, and the power of circumstance.
For historical fiction:
* Life on the Mississippi: A semi-autobiographical account of Twain's experiences as a steamboat pilot on the Mississippi River, this book is both captivating and historically significant.
* Roughing It: A humorous and often poignant account of Twain's experiences in the American West during the 1860s.
Ultimately, the best "interesting" book by Mark Twain for you depends on your individual preferences. I encourage you to read a few different works and see which ones resonate with you the most.