You didn't give a price range, but from Bayview to Leslie there are at least 50 different Asian restaurants (mostly Chinese) that vary from expensive and excellent (O-Mei, Ambassador) to much cheaper and still very good (Richmond Court, Saigon Star, John's BBQ). The Chinese malls at Times Square and Jubilee Square have many different choices available, and virtually all have many vegetarian options available.
If you must go North American, the restaurant plaza at Hwy 7 and 404 offers pedestrian choices like Jack Astors, but also has a Keg, Japanese, Indian, and Italian choices. Haven't tried them all, so can't give any reco's (although the Keg, like all Kegs, is predictable and if you opt for one of the "classic" meals, not at all a bad value).
Hope this helps.
Actually, for North American cuisine, I second Kevin's recs. There is a cluster of restos on hwy 7 (west of the 404):
on the north side - a variety of chain'type restos - Jack Astors, Keg, Alice Fazooli's, Moxies and then quite a few that I cannot recall. There is also a Host in this area, and I prefer this particular location above and beyond the downtown location (haven't been to the one in mississauga tho). There is also a slew of other places - greek, sushi, etc.
On the south side of Hwy 7 there is a Baton ROuge (not a good veg option) and this place called Brix Nappa Valley Wine Bar....intresting place, sort of. A tad overpriced and generally, the service is lacking. BUT, the food is actually quite good and they tend to offer a little bit of variety compared to the other places in the area. They make some fantastic appetizers.