In a high-level Pentagon memo, it was revealed yesterday that the recent laying off of more than 2,500 Defense Department employees has resulted in a 31 percent increase in video rentals at Washington-area Blockbuster video stores. 'I rented 12 Monkeys last night,' said now-unemployed Gen. William A. Patterson. 'It was pretty good. Did you ever see Muriel's Wedding? I may rent that tonightI heard it was good.' Patterson went on to recommend that the U.S. maintain a hard line against Iraq and Denis Leary's The Ref. 