My brother-in-law lives in Jefferson County Ohio (my husband is from there too...not that it really matters) and they have an IG vinyl pool. They generally drain below the skimmer and add antifreeze to the lines and cover with a winter safety cover. I'm not sure what they do for leaves and other debris on the cover in the spring though.

In the spring for start up they just dump in (and I mean that literally...they're not that "up" on their pool chemistry and it's not uncommon for them to have algae issue all season) liquid chlorine from the pool store.