Some say you should leave the mower on the highest setting for your last
cut to avoid winter kill (my husband) and others say to cut it as low as
possible. Who is correct?. I do my last cut when all the leaves are on
the ground, then I use the mulching mower...

According to a Ortho lawn care book, we are supposed to leave cool
season grass to the maximum mowing height in the last mowing of the
year. That will be something like 3" for Kentucky bluegrass, and that
is the height that I am going to leave at in my lawn.

Hope this helps.

Jay Chan