This is a solid collection of myths, folk tales, proverbs, riddles, etc. (Though it is mostly just folk tales, as the title would suggest.) Most stories in this collection are short, entertaining reads.
Some could easily be Zen koans, like The Kind Man. Others such as The Frog, The White Rooster and The Castle in the Lake feature human to animal (or vice-versa) transformations. These could easily be Native American, early European, or straight from Aesop himself.
Perhaps the most 'important' story here is the origin story of Gesar, who is something like a King Arthur figure for Tibet, though Gesar has both supernatural origins and powers. The book says that in Tibet, the fable of Gesar is often orally transmitted, typically over weeks of storytelling!
My favorites were the proto-Buddhist tales featuring the Buddha himself (though in a previous life), The Kind Man, and the tales of zoological transformation.