If you like the cold or not, Toronto is perfect. You can skate outdoors, walk threw a nice snowy park, toboggan on a great hill at Danforth & Broadview, which has amazing views of the city's skyline. The restaurants are some of the best in the world. There is so much culture in the city that you can eat at a different restaurant from all four corners of the planet every day.

There tends to be more to do in the summer months than in winter ( but it gets very hot in July & August).

Either way, with the Toronto Island only a 10min ferry ride from downtown and the amount of festivals going on in the city, you can never get bored.