I have run snow, ice, etc with all sorts of tires in my life; AT's, All-Seasons, Snow Tires, Snow Tires + Studs. If you are encountering hard/black/slick ice, there is NO substitute for STUDDED snow tires, NONE. It will improve your on-ice performance a hundred times over. Mind you, you still have to be a bit CAREFUL and SLOW DOWN, but with good STUDDED snow tires, you should be able to drop er in 4x4, and if you go easy on the throttle/speed, you should be able to handle the slickest ice known to man with confidence and ease.
The best tires for a Tracker in the Canadian winter, IMHO, are Nokian LT235x75 R15's with studs. That's what I run on mine, and they work great. I can pull iced over inclines in 2wd that guys in 4wd with non-studded tires can't make it up. Heck, earlier this year, I ran across a poor chap in a full-size Ford that couldn't make it up the iced over 7-ish % grade (forestry road). I whipped out the tow strap, dropped er in 4low, and hauled his butt up and over the top (about a 1/2 kilometer climb), didn't even spin the tires all that much.
Go buy the studded tires (Nokian's, I recommend), and don't look back -- you'll be glad you did.