k first off i go to laurier for economics (which is very similar to business at our school), so i'm slightly biased... but here is the breakdown of ontario schools in my opinion (just for business/commerce programs):
laurier - great bba program, everyone is very nice in my experience, the parties are good, and the degree is very well recognized in the real world. Laurier has an excellent reputation for producing high quality students and their BBA is like the pride and joy of the school. The only drawback is that you're not garunteed co-op, you have to apply after first year but as long as you have the min 70 average (which you need to progress anyways) you're pretty much a shoe in. Also the school is smaller compared to other so you get to know people faster and you'll allways see people on campus you recognize. I'm in co op too and i highly reccomend it no matter what school you attend, it gets you jobs with awesome pay and puts you a step ahead of everyone else trying to get experience once you're out in the real world. Also laurier business lets you specialize (although most schools do i think) to choose what stream of courses and subjects you'd like to focus on after second year (eg marketing, accounting, finance, HR etc)
now the next few i have less info on obviously, but here is my general knowlege on their business programs from talking to people at my company and others i know:
carleton - good school (i have a friend that goes there for arts), however if you're gonna go to ottawa for busniness u ottawa is better from what i understand (but i would suggest looking further into that one). Carleton is also notoriously hard to transfer out of if you're ever looking to switch schools after you do a year or whatever.
u ottawa - good school. They offer all classes in both languages i think if you're into that. Strong rep and offer co-op
ryerson - i looked at their business programs when i was applying, and they are up and coming. I've talked to people that are there and they like it, i just think the school's business program gets overshadowed by york and UT. I don't know if they offer co-op either
mac - great school and they have an awesome business program from what i understand. They also offer co-op. Nothing bad i can really say.
guelph - good business program, however the focus of the school is arts and sciences. I don't know if they offer co-op either, but i've never met a co-op from guelph
western - great reputation in the business world. I went to western for the first time and its quite large compared to laurier. The Ivy business program apparently really pushes you towards I Banking, so if you're into finance and all that jazz that is probably your top pick. The regular business program is good too. I have no idea about co op at western
Hope that helps, pm me if you have more questions
good luck with the decision