You drive along the shore on the 1000 Islands Parkway or take a boat ride out of Gananoque and see the islands. When you're on the bridge you can't stop. It's not worth it. There can be large delays at the border as well. If you want to do a side trip, you can go to Ottawa and see the museums and capital stuff (north from Brockville). Or get off at highway 37 and go north to Plainfield and buy the best cheddar at the Mapledale Cheese factory store. The ride from Ottawa to Montreal along the Ottawa River is nice on the Quebec side or go to the Laurentians from Ottawa and head down into Montreal. The 401 from Toronto to Montreal is absolutely nothing. Did you consider the train or flying on Porter?