Matt Beleskey and Ryan Getlaf also scored for the Ducks and Jonas Hiller had 25 saves on 27 shots on goal.
Selanne, who had been out of action since fracturing his left hand Dec. 3, opened the scoring at 12:10 of the first period with a wrist shot off a pass from Petteri Nokelainen.
Beleskey and Getzlaf scored in the second period to pad the Ducks' lead to 3-0.
Nashville made a game of it with two goals in the third period. Hornqvist scored on a power play just 45 seconds into the period, but could not get past Hiller until Dumont scored with 3 minutes to play.