this will answer alot of your questions.
I grind my flax and hempseed,
some folks use the oil (keep refridgerated)
and the links inside will get you both.
unground seeds pass thru completely undigested,
of no benefit at all.
it is easy as heck to grind seeds yourself as needed.
REAd the link inside / the blog post that you will
come to , amny folks use both oil plus ground seeds.
i keep my fresh ground seed in a shaker in fridge
and sprinkle on most everything.
Takes all of 30 seconds to grind your own.