The "best" theatre schools (this is, of course, subjective) would be NTS, York, UBC, McGill, Alberta and (for tech, perhaps not for acting) Ryerson. You might also wish to consider the University of Toronto, the University of Victoria, Dalhousie or Ottawa.
It bears noting that all of Canada's mainline undergraduate universities are large and public: with the exception of NTS, all the ones I've listed have at least 10 000 undergraduate students and full Liberal Arts and Science faculties in addition to their Fine Arts programming.
My understanding is that York has the strongest dance program in the country, but--again--this is somewhat subjective.