Befitting Tuesday’s election of the first baby boomer president, MTV will hold “The Pre-Inaugural Rock ‘N’ Roll Ball” on Jan. 19, a day before Bill Clinton takes office.U2 is among the acts expected to perform. MTV is using the ball to applaud the young voters who turned out in greater numbers for this year’s election. The cable music channel will invite Clinton and his family as well as Vice President-elect Albert Gore, his wife Tipper and their children to the event. Both men participated in MTV’s much heralded “Choose or Lose” programming leading up to the election, and vowed to come back to the network if elected. The music video network will coordinate the event with the Democratic Party Inaugural officials as well as those from Rock The Vote.