Thanks for all the great advice!
To answer some questions: I live in DFW TX, but have trips further west planned (Rockies most of all, as well as Big Bend). I cannot fit anything but a thin pair of wicking socks in my running shoes - which is the main reason I wanted a pair of hiking shoes/boots. Also, we (bf and I) do most of our hiking during the fall/winter b/c it is so miserably hot during the summer here. And not being able to fit any good socks into my shoes makes my feet freeze.
I think that kind of touches on the when and where question!
So the general consensus seems to be taking a minimal approach on footwear (go with trailrunners if possible) and have good socks. Wool, wicking, and waterproof if needed. Sounds easy enough
One problem I do have is weak ankles. I ride horses and I'm constantly in paddock boots (which have ankle support). Walking around in those since I was 4 haven't given me much ankle strength at all, something I know I should work on if I want to go on longer backpacking trips.