Kingston: This southern extension of the Canadian shield is nice with all the limestone. The last few times I went there, it had a lot of nice shops and restaurants downtown, although I don't know what it's like now. It also has a great music scene.
Peterborough: Another great music scene and more interesting shops. Peterborough is one of the few places where the downtown is still busy. The Peterborough Zoo is always a hit, as well as the Indian River Reptile Zoo east of the city.
Toronto: As Jan Morris said, Toronto has just enough of everything. While not London, Paris or New York, it isn't Columbus, Ohio or Paduca, Kentucky either. There are just enough theatres, museums, ethnic restaurants, sporting events, and other attractions.
Hamilton: Spent some time there, but my exploration of the city consisted of going to Cops' Colosseum to see a Hamilton Bulldogs game when I lived in Brantford. I'd like to see more of this interesting city because it seems like a miniature Toronto, multiculturalism without the big city hassle.
Brantford: As stated in a previous post, I spent time there a while back. Didn't see much of the town of Brantford, but saw many of the surrounding area, such as going to the Simcoe Fair, the Simcoe Lights and other places. I'd like to go back there and explore Brantford and area more, but my impression from the time I spent there was that it was like southeastern Ontario in that all the towns are unique.
Bradford: A bit of a weird-seeming city, but anyone who visits has to check out the Bradford Marsh.
The Muskokas: Cottage country. Southeastern Ontario tries to be cottage country but the Muskokas have a lot more wealth and a lot more interesting things to do. They beat us to the punch.
New Liskeard: Has a bit of a wild west feeling. The French influence also helps make it interesting.
Killaloe: Located in the Ottawa Valley, this little town also has a wild west feeling. Definitely have to go back there someday.
Barry Huronia and the Bruce Peninsula: This area proves money buys happiness. With it's fertile farmland, tourist industry and nuclear plant, there's an openness and a friendliness in the people. Statistically, there are lesser amounts of social problems than in other parts of the province.