On the day Georgia Rep. Newt Gingrich was unanimously elected Speaker by his GOP compatriots in the House, Clinton allies exploded over his allegation yesterday on NBC's "Meet the Press" that a quarter or so of the White House staff had used illegal drugs. The major riposte came from Chief of Staff Leon Panetta, who denied the accusation and said he detected a "troubling pattern" akin to North Carolina Sen. Jesse Helms' recent verbal firebombs. Panetta then vowed the White House "cannot do business" with Speaker Gingrich if he lobs unsupported allegations. "The time has come when he has to understand that he has to stop behaving like an out-of-control radio talk show host and begin behaving like the speaker of the House of Representatives," Panetta said. First Lady Hillary Clinton merely labeled the remarks "unfair" and said she hoped they were "a momentary lapse." Among other Gingrich comments Sunday: the United Nations is a "totally incompetent" body, and that Mrs. Clinton -- who last week called Gingrich's proposal for orphanages "absurd" -- should rent a video of the 1938 film classic "Boys Town" to assuage her doubts.Republican House members today also elected two Texans to key leadership posts -- Richard Armey, 54, as majority leader and Tom DeLay, 47, as whip.