Peterson's scoring runs were from 22 yards and 1 yard.
Favre threw 29 passes, completing 20, one of them an 8-yard scoring toss to Jeff Dugan.
Ryan Longwell kicked 22- and 35-yard field goals for the Vikings (8-1), who led all the way.
Minnesota's Sidney Rice grabbed seven passes for 201 yards.
Rookie quarterback Matthew Stafford passed 8 yards to Will Heller for a touchdown and Jason Hanson booted a 38-yard field goal for the Lions (1-8).
Stafford finished with 29 completions in 51 throws, totaling 224 yards.