You have nearly 14 days and that should be enough to have a feel of Niagara, Toronto, Montreal and Quebec city. Niagara apart from the waterfall has a great golf course. You could also visit the Butterfly Farm, a few kilometer east of the falls on the way to Niagara-on-the-Lake. Which is a quaint little pretty town one should not miss. Drive through the town and have lucnh at one of the many fancy restaurants this little town boasts. On way to Totonto, you could go through the wine country and taste free wine at some of the vinyards.

Toronto has nothing omuch 0of historical importance but is a great and vibrant city with over hundred ethnicities making it their home. You can try any cuisine you can even think of. Apart from that, you could also visit Toronto island, or have a cruise-dinner on one of the ships anchored at the lake.

Montreal is a part town. Great food, music and the grand cathederal. There is a lot of things to see and do in Montreal.

Quebec city is the most "european" city in North America. You will love its narrow lanes, little shops selling fashion statements and friendly people.

Happy traveling some of the nicest places in canada.

Depending on the driving route you choose, you might even want to add a couple of days in Ottawa, our nation's capitol. Perhaps 2 days (max!) for Niagara, then 3 days in Toronto, 2 in Ottawa, 3 each for Montreal & Quebec. That would really give you the highlights of each city, and make the driving time a little less cumbersome.