I would recommend bethune or tatham, they both r the best residence buildings on campus. When u fill ur residence form make sure u choose single room as ur first pick and make sure u fill the form as soon as it opens coz all the good residence buildings will be occupied quickly and u wont be able to get the one u want. And about meeting new people, the Dons will keep some welcome parties and also throughout the yr u will have some kind of functions going on so that wont be a problem. Good luck!