Shocker for new First Lady Laura Bush when she sat in her new DC office for the first time and tried logging on to the official White House Web site on her computer. Instead of typing the correct address — www.whitehouse.gov — Mrs. Bush made a slight mis-type and . . . YEOW!! Up popped a sleazy porn site offering “Excellent & 100 Percent Fresh FIRST LADIES.” Red-faced Mrs. Dubya called a staffer to scrub her screen and renavigate the Net!