Universal Studios said on Monday that it would stick with plans to show an adrenaline-pumping trailer for "United 93," its forthcoming thriller about the passenger revolt on one of the planes hijacked on 9/11, despite qualms from some moviegoers and families of 9/11 victims. Adam Fogelson, Universal's president of marketing, said the trailer, which was pulled from AMC Loews Lincoln Square 12 Theater in Manhattan on Saturday after complaints from patrons, would be shown only before R-rated movies or "grown-up" PG-13 ones. He said the trailer was created to give a candid sense of the film itself, which opens at the end of the month. Sharon Waxman reports.