Sidney Crosby and Evgeni Malkin also scored for Pittsburgh. Letang also had an assist.
David Legwand, Cody Franson and Patric Hornqvist scored for Nashville.
BRUINS 4, CAPITALS 1
In Boston, Nathan Horton scored his fourth goal in five games, and Tim Thomas made 38 saves as Boston won its fourth game in a row.
Michael Ryder and rookie Jordan Caron also scored for Boston. Patrice Bergeron earned his first points of the season with a pair of assists.
RANGERS 2, MAPLE LEAFS 1
In Toronto, Ruslan Fedotenko and Artem Anisimov scored first-period goals, and Martin Biron made 24 saves in his New York debut.
Biron was strong in goal for the Rangers, who earned their first victory since opening night at Buffalo.
DEVILS 3, CANADIENS 0
In Montreal, Martin Brodeur made 29 saves for his 112th NHL shutout and Jason Arnott had a goal and an assist to lead New Jersey.
Brodeur stuck out his left pad to stop Mike Cammalleri early in the third, protecting a 2-0 lead on his way to his second shutout of the season and 604th career win.
RED WINGS 4, FLAMES 2
In Detroit, Johan Franzen's third-period goal broke a tie, and Henrik Zetterberg and Todd Bertuzzi both had a goal and an assist to lead Detroit.
Nicklas Lidstrom also scored for Detroit. Jimmy Howard made 34 saves.
DUCKS 3, FLYERS 2
In Philadelphia, Ryan Getzlaf scored with 2:14 left in the third period to power Anaheim.
Lubomir Visnovsky and Jason Blake also scored for Anaheim.
STARS 4, PANTHERS 1
In Sunrise, Fla., Tom Wandell scored two goals to lead Dallas.
Steve Ott and James Neal also scored for Dallas. Jamie Benn had three assists.
ISLANDERS 3, LIGHTNING 2 (OT)
In Tampa, Fla., Matt Moulson scored a delayed, video-reviewed goal in overtime to lift New York.
Moulson was credited with a goal at 1:56. Officials reviewing the play ruled that the puck went off the glove of goalie Dan Ellis and completely over the goal line before Ellis swiped the puck back into play.