The University of Ottawa has a lot of things going for it -- a great city, lovely campus, good connections for international, NGO and gov't work, solid roster of profs and research chairs (in my subject at least) and competitive funding. The administration there, however, has so many problems that it might severely derail your uni experience. Think classes getting cancelled at the last minute, poor communication about university deadlines and regulations, and some seriously questionable responses to campus issues.
As with any university, but particularly with U of O, it might be a good idea to look into campus culture and some of the ways the university has been in the news in the process of making your decision.