1) Adrian Peterson
This matchup always brings me fond memories of my first ever FanPosts here in 2009, when I was an avatar-less putz thinking I knew things about football. And my first key there was the same as the first key I'm providing here, because while a few years have passed since then, the focal point of the Vikings offense remains the same - Adrian Peterson is a monster disguised as a football player. And he's a monster that's played very well against the Bears.
2) Jared Allen
I think by now Bears fans are extremely familiar with the pass rush of Jared Allen (and Brian Robison). But with a pair of new bookends on the Bears offensive line (and starting), hopefully Allen won't repeat the 3.5 sacks he picked up on J'Marcus Webb. Jordan Mills had a great debut against the Bengals, and Jermon Bushrod looked pretty good against Michael Johnson. They both will need to be ready - Bushrod's done well against Allen in the past, but can Mills hold up against Robison?
3) Stephen Paea
Paea had a nice game on the defensive line against the Bengals - which is more than we can say for most of the rest of the unit. Against one of the best running backs in the game, Paea has to get good penetration and disrupt Adrian Peterson's running lanes.
Peppers can help by having a much better game over his effort last round. He'll draw the matchup against Matt Kalil, and he'll have to make a play or two to have an impact.
5) Get an Early Lead...
The Bears had a rough first half against the Bengals. Getting an early lead would give the offense confidence they can do whatever they need to, but more importantly than that...
6) ... And Make Christian Ponder Beat You
With an early lead, they can put the screws to the Vikings and make them either commit heavily to using their best weapon (while eating the clock), or conserving the clock as best they can and getting the ball in Christian Ponder's hands. With a bad enough game, Ponder could end up benched for Matt Cassel (not likely, but possible). But barring that, Ponder's still a first-round quarterback that hasn't played like it at (many) times. The Vikings do have a passing game, with Greg Jennings, Jerome Simpson, Kyle Rudolph, and Cordarelle Patterson. It's just a matter of Ponder getting them the ball. Take Peterson out of the game, and make Ponder show he can do that.