Touring the City of Toronto and the Greater Toronto Area (GTA)Disclaim: Since I've answered similar questions on the web so many times in the past, I decided to put together this FAQ here for your convenience as well as mine. :) (Here is a more detailed summary on Toronto Chinese food written by someone else)

First about downtown.

The financial district is only window-seeing except for the Exchange Tower (King St/York St) where you could watch for some fun in the room (but the scale is considerably smaller than New York Stock Exchange).

Centre Island is another downtown spot at the harborfront (Bay/Queensquay), from where you can enjoy the skyline of the city across Lake Ontario. The ferry is about $10 for a non-senior adult and the ride is about 10 min one way.

The Casa Loma castle is in midtown, all the way to the North end of Spadina Ave. The ticket is about $15 to enter the castle and the underground tunnel.

The Royal Ontario Museum (Spadina/College) and Arts Gallery of Ontario (East end of the West Chinatown in downtown) are also must-sees.

For other downtown/midtown/uptown entertainment, use toronto.com or the City Site as your starting guide.

Now for spots in the surrounding areas/cities, you'd better rent a car rather than taking TTC (Toronto Transit Commission) buses/subway to save you time (Toronto is flat and big, like Chicago), if you stay in downtown; or taking the GO train if you stay in the suburb (more trains if close to lake shore):

If you do not hate animals, Toronto Zoo is in Scarborough, on the Northeast corner of the megacity (a.k.a. GTA) and ticket is about $20? If you go to the big Falls, which is 1.5 hrs West of Toronto, you could also visit Marineland Canada just by the Falls. Another one is African Lion Safari, a much more fun place with wild animals in Hamilton (North) between Niagara and Toronto.

Now move on to Chinese (or mostly Cantonese) food.

If you come from a place where Chinese restaurants are at most Ok but not great, then any chinese restaurant run by a Joe in downtown would satisfy your stomach needs to your heart's content. ;)

But if you come from places like SF or NYC, you should really go to Scarborough, Markham, or Richmond Hill for even better tasting c-food. I always recommend restaurants along Highway 7 to new visitors (easy to find anyway). Again, rent a car for such trips.

Also when you go up North (or Northeast), you can do some Chinese shopping. You'll see a chinese shopping plaza at each major intersection in the above-mentioned cities. The biggest one should be the Pacific Mall (太古金王朝), with a few satellite malls in the same plaza. That's located at Kennedy and Steels (border of Scarborough and Markham).

You could either rent a car for the first couple of days, or during the last couple of days, for the purpose of going afar. And for the other couple of days, stay around downtown, relax and enjoy.

Check out travelocity.com or trip.com for cheap tickets, and don't buy Air Canada as they are more expensive (oops - hope my wife won't read this!! ;)). They have shuttle and even city buses from Pearson airport to downtown (with city bus you'd have to transfer to the subway). I would check with the hotel to find out info on buses to the Falls.

(I think I'll save this and set up a FAQ webpage soon ;)).