I haven't really been around Toronto as a tourist, so I'm afraid I can't recommend hotels, but I can recommend a few sights to see: you'd want to go up the CN Tower, first of all.
Not if you have an extreme fear of heights, but you know. There's a glass floor that's pretty cool. The ROM - Royal Ontario Museum - is nice if you like museums. If you're a baseball fan and are here around the baseball season, you can see a game at the SkyDome, which is right beside the CN Tower (it's been renamed the Rogers Centre a few years ago, and people call it by both titles).
If you like theatre, you could see a play downtown. If your story is set right now... The Sound of Music is playing at the Princess of Wales theatre and it's just an amazing show (tickets range about $25-$100, though, depending on where you're sitting).
If you want to go shopping, the Eaton Centre is a great mall downtown (and I also like Yorkdale mall, which is further north).
Also - do not drive downtown. Get a TTC pass - it'll get you around just fine. (TTC = Toronto Transit Commission, which runs the subway and buses.) The subway system is pretty easy to navigate.
Lake Ontario is south, as is the CN Tower and the downtown area - so basically, south is downtown, north is the suburbs. Yonge Street (the longest street in the world
) runs the length of the city from the lake and divides into east and west.
If you have any particular questions, let me know.
Julie