Two things to beat the Vikings. First, win the turn over battle. The three games we lost this year are the only three that we didn't get a turn over against the opposition.
Secondly, play pass defense, and let the competition implode, when they make errors, or have penalties that force them into passing. You're always prepared for it. The objective, with any defense, is to stop teams from scoring, not to stop them from running up yardage that nets no points. The Vikings run the ball just under 43% of the time, so even though they are a decent running team, they pass more than run. You don't need to stop every run, just enough to force them into passing the ball.