I'm not really a car guy, so take this as you will.

I'm biased towards the Tacoma, Explorer (older generations), maybe the XTerra (I like it's looks, but it was too similar to the Explorer I was trading in), the 4-door Jeep, and maybe the Raptor or H1. Ideally, all in 4wd. If you can get it, the Toyota Hilux too. If security is a concern, buy a cap or camper shell. But realize no vehicle is 100% secure.

Lots of room in them, obviously various capabilities, but all proven platforms. Not great milage however - I think the H1 was 8mpg with diesel. By comparison, my Tacoma, 2wd/4wd and a 3" lift, gets consistent 21-22mpg highway. The Explorer I had (1998) got around 16mph.

If you're going something smaller, I'd go with the Suburu, just based on my experiences. I spent a month in AK a few years back (the thread is somewhere here), and they were everywhere. Pretty much, the town wasn't plowed, so the streets were ice. Everyone had on snow tires and was driving 20-30mph on the ice roads w/ no problems. Nearly every car was a Suburu, usually w/ a lot of snomobiles and ATVs too.