With a new set of forward lines, the Rangers played sound defence and snapped a two-game losing streak.
Michael Nylander gave the Rangers a short-lived lead in the first period before Marc Savard tied it less than a minute later. Straka put New York ahead for good in the second with his 24th goal.
Ortmeyer, playing in his sixth game after missing 40 while recovering from a pulmonary embolism, netted his first goal on his first career penalty shot. He was pulled down during a short-handed breakaway, and after receiving advice at the bench from enforcer Ryan Hollweg, beat goalie Tim Thomas with a head-and-leg fake and then a deke with 2:47 remaining.
That was enough for the Rangers, who had allowed 11 goals the previous two games.
Rangers captain Jaromir Jagr, who'll stay home from the all-star game to rest, had one assist and picked up a roughing penalty during an angry, shoving exchange with Paul Mara in the second period.
Straka restored New York's one-goal lead 5:52 into the second. Although he wasn't picked Saturday for the NHL all-star team, Straka is tied for ninth in the league in goals and 10th in points. He has six goals and nine points in five games.
Unlike Thursday when the Rangers fell behind by five goals in the third period to Ottawa before rallying with four in the final period of the 6-4 loss, New York took an early lead on Nylander's 15th.
Marcel Hossa banged at the puck as it bounced by Thomas, causing it to squirt out to Nylander for a quick shot into the open left side 10:34 in.
Before the goal announcement was complete, Savard - the Bruins' leading scorer - tied it. Brad Stuart's shot struck the skate of New York defenceman Thomas Pock and caromed off the leg of Savard, who wasn't facing the net but scored his 16th goal 38 seconds after Boston fell behind.
Boston has been outscored 35-14 in its past seven games, going 1-5-1. But Savard has eight points (four goals, four assists) in four games.
Rangers goalie Henrik Lundqvist looked steady after absorbing the tough-luck loss to the Senators, despite allowing only one goal on five shots in relief of Kevin Weekes. Lundqvist made his ninth start in 10 games and stopped all but one of Boston's 25 shots.
Thomas got back in goal after sitting out the Bruins' 5-4 shootout loss at home to the New York Islanders on Thursday and made 35 saves. That wasn't enough to keep him from his fourth loss in five games.
In that span, Thomas is 1-4 with 23 goals against.
Notes: Shanahan was chosen for his eighth all-star team. Boston D Zdeno Chara was picked for his second. ... The Rangers took a season-high 22 shots in the second period. ... Boston lost all four to New York last season. ... Jason Krog, claimed off waivers Friday, made his Rangers debut. ... Ortmeyer earned his first two assists this season Thursday.