Namakura Gatana / The Dull Sword (1917) is a silly and childish story, and a display of animation capability (rather than telling an immensley deep story).
Usagi to Kame / Hare and the Tortoise (1924) demonstrates interesting (and most-likely highly revolutionary) three dimensional effects while recreating a common and conventional folk-lore (perhaps less overused for its time).
Urashima Tarou (~1918) is a recreation of a Japanese folk-lore which was more prevelantley known in Japan, but no so commonly in the West; without which interpretation of the story becomes confusing. For brevity, here. Nonetheless the animation itself is sparse, and difficulty exists in translating a longer story in such a short time-span.