I have no first hand experience w/ snows on a pickup. But I know everyone and their brother runs Blizzaks 'round here. My buddy runs a set of 4 on steelies on his sedan and swears by them. They are studless, which means they do fine on dry pavement too. Studded would be a better choice for heavy snow, but not-so-great for those days between storms.
Faster wear is the biggest downside to the Blizzaks; they wear fast. But that is standard fare for snows.
Cooper makes a set of snows that I hear good things about too.
An alternative is going for a good set of all-terrains. Not quite as good as dedicated snows, but not bad either. The BFG ATs I have on my truck now are light years ahead of the all-seasons I've used before in the snow. I think they are a nice comprimise as they wear well in year-round use. I'm at 41k miles now on a set and expect to get well past 50k miles.
As for weight in the bed, I would run at least 200 lbs in a 4x2. I used to run 240 lbs by way of four bags of sand at 60 lbs each. The upside of sand is that you can tear open a bag and use it for traction if you get stuck on ice. Done that once or twice..
2003 Ford Ranger FX4 Level II - Silver - Stick - fuelly
2009 VW Jetta SportWagon SEL - Grey - Stick - fuelly
2001 Suzuki Bandit 1200 - Red
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