I started consciously trying to read more old books in the last year or two and I've discovered that I love adventure stories! Jules Verne, Sir Walter Scott's Waverly novels... Winston Churchill's "My Early Life" is nonfiction that might as well be an adventure story, haha.
For humour it's hard to go wrong with P G Wodehouse; he wrote much more than just the Jeeves stories.
Recently I read through all of Lucy Maud Montgomery's collected short stories (the author of Anne of Green Gables among many others).
Dracula was a great read and genuinely spooky, ditto Henry James's The Turn of the Screw.
Sometimes I go to Project Gutenberg, hit "random" and download anything that catches my eye :)