James finished with 19 points for the Wizards, while Young - who set career highs in three of his past four games, including 33 points against New York on Wednesday - finished with 13.
The Knicks were led by Al Harrington's 18 points. Wilson Chandler had 16 and David Lee had 15 points while matching a career high with 21 rebounds.
The Wizards scored just their fourth win in the last 21 games after a topsy-turvy night that included holding New York to 14.3 percent shooting and 12 points in the second quarter.
Washington led 49-37 at halftime.
The Knicks, who were attempting to sweep the Wizards for the first time since the 2003-04 season, outscored Washington 29-9 to start the third quarter. They led 67-58 with 3:09 to play, thanks to 11 points from Chandler.
The Wizards cut the lead to 72-70 after three quarters, with Jamison scoring 10 points out of halftime.
Washington coach Ed Tapscott was upset after watching his team allow 128 points to the Knicks in their loss in New York on Wednesday night, and wanted to make sure the Wizards weren't seduced by New York's fast tempo.
In the first three games against the Knicks, Tapscott's team allowed 114, 122 and 128 points.
"I'd say there's a pattern there," Tapscott said before the game. "Patterns shouldn't surprise you."
Notes: The Knicks were without F Tim Thomas, who was out with flu-like symptoms. ... C Eddy Curry missed his fourth straight game with a sore right knee. ... F Danilo Gallinari, who hadn't played since Oct. 31 with a sore back, was in uniform but did not play.
... The Wizards handed commemorative issues of the Nov. 5 Washington Post marking Barack Obama's election.