Your plans sound great. I've always preferred the Plateau area as a base - it's generally quiet, safe and very charming. However St. Denis is probably the liveliest street in Montreal, so if you are staying on that street it can get pretty noisy. You mentioned you might be renting bikes. You can certainly bike much more than just the parks as there are safe, well marked bike paths throughout the city. In fact, the bike ride from the Plateau to the Botanical Gardens is a piece of cake. The past few years we wouldn't dream of going to Montreal without our bikes - it's how we get around.
Yes the most interesting part of Quebec City (the old city) is quite small and walkable. However QC does have a 'real' downtown and lots of non touristy neighborhoods - nice but not particularly memorable. One thing a lot of people miss out on is the observatory at the top of one of the taller buildings just outside the old city. The changing of the guard is also fun and a good photo op.
As for Baie-St. Paul, one night in this very scenic area would be a nice change of pace from the cities.

Thank you so much! Question for you: if we can get a room when we want to go, we're thinking of staying at Auberge de la Fontaine near the park in the Plateau. It's 15 min. walk to the Metro but the owner said it's near tons of restaurants and bars and not too far from St. Denis.... your thoughts?

I've never stayed at Auberge de la Fontaine, but I know where it is. The neighborhood is very nice - quiet and upscale but just a short walk from all the action on St. Denis, and all the fun byob restaurants on Duluth St.

That's what I thought - thank you very much. Any particular neighborhood restaurants or bars you prefer and would recommend? Any in Old Montreal or Downtown? Iso appreciate your input.

There are so many good dining options in this area. Here are some of our favorites, all moderately priced:
Le Jardan des Panos - Duluth st. Byob Greek with a great outdoor patio.
Lotus Bleu - Duluth St. Byob Vietnamese. Outdoor patio.
Spaggios - Duluth St. Byob Italian. Outdoor patio.
Khybler Pass - Duluth St. Afghan.
L'Express - St. Denis. French
Cafe Cherrier - Cherrier. French Bistro
Le Grand Comptior - Sq. Phillip. French Bistro.
There are lots of bars on St. Denis, St. Laurent, and Crescent. Many have live bands.
Just fyi, your hotel is right on a main bicycling hub.

My husband and I just returned from a week in Montreal. In May, Fitz and Follwell added a walking tour called Flavours of the Main and it was incredible. For $98/person this is a 5 hour tour that starts in Chinatown and you eat your way up Saint-Laurent (and a few side streets), ending at Jean-Talon Market. We made 15 stops in all and thought it was a great bargin considering all of the food we ate plus we received a 1 day metro pass to keep when the tour was over.

We also saw Cirque du Soleil. We had never been to one of their shows and were absolutley mesmerized for 3 hours.

We stayed at Place D'Armes Hotel in Old Montreal - lovely. Our favorite restaurants in Old Montreal were Stash Cafe (Polish) and Olive et Gourmando (breakfast, bakery, lunch).

Thank you both very much for all the great info - I am sure it will come in handy.

I think you mean you want to go to the Biodome plus Botanical Gardens. The Biosphere is in another area of the city and I think it is much more interesting than the Biodome. They are all easy to get to with public transportation.

we have stayed at Auberge de la Fontaine and would recommend it. It is definitely near all the restaurants on Duluth and others on Rue Rachel and St Denis. Many are BYO

There are good bike paths along the Lachine Canal.

There are lots of threads on what to do and where to eat in Montreal and Quebec City. I posted a short TR detailing things we enjoyed doing in QC last year.
http://www.fodors.com/community/canada/quebec-city-three-day-visit.cfm
I have posted a lot on threads asking about Montreal but have never done a formal TR. We live about 3 hours away and go there often mostly on weekends.

"BYO" deserves a quick translation. "Bring Your Own (Bottle)" helps you save big money on wine. Often the bistros that permit this approach are small and cannot afford the expense of setting up their own bar. But the food can be charming. Some Internet research will show a number of good places in the Plateau and Mile End. Corkage fees are rare. In French, which you will see in these areas, "Apportez votre vin." Unfortunately a New Yorker may be startled by the prices charged in the government booze stores (SAQ). Corner stores do sell wine but are limited to the cheap stuff, usually from Southern France and Chile.

By the way, the park that is "just like home" for you is Mont Royal, designed by the architect of Central Park. Different physical attractions, obviously.
Basic tourist information, including an extensive guide to events, at the city's site http://www.tourisme-montreal.org/

I get promotional emails from Auberge de la Fontaine and a recent one describes a promotion connected to the Small Hotels of Montreal 25th anniversary
http://www.aubergedelafontaine.com/montreal-hotel/package-small-hotels-montreal/?utm_source=All&utm_campaign=Newsletter+May&utm_medium=email
The hotel also participates in a promotion called Sweet deals

Some other small hotels are part of the association and are in or at the edge of the Plateau.
http://petitshotelsmontreal.com/en/petits-hotels-montreal-centre-ville.php

Thank you for your responses! Yes - I meant the Biosphere! We've already booked our room at Auberge de la Fonataine and it seems like a perfect location. As for being startled at wine prices in gov't stores.... nothing surprises us anymore! I'm also looking forward to some of the microbreweries I've read about. I love that we'll be near your "Central Park." CP in NY is just wonderful (as is Riverside Park on the Hudson River). I think our 4 nights in Montreal will be fun and wonderful along with our 3 nights in Quebec City. Just looking at online photos I can tell it will be a special trip. Thank you again for your time and your suggestions!

Wine prices at the SAQ's are slightly higher than in the USA, but they have a very good selection of wines. Surprisingly, some of the 'cheap' California wines are more expensive than some French wines. Montrealers are serious about their wine, and on a Friday or Saturday evening the lines at the register can wind to the back of the store.
Just to clear up the park thing - Auberge de la Fonataine is directly across the street from Parc La Fontaine, a very pleasant park and one of the largest in the city. It is not near Mont Royal park (the 'Central Park' of Montreal), which is halfway across the downtown to the west.
In addition to microbreweries, there are many very good Canadian beers to be found that are not available in the US. Boreal Russe is my favorite!
The Biodome is at the Olympic Stadium. The Biosphere is out on the island near the old port.

Laurie--glad you are going to the Biosphere. This is what I wrote about it after a visit there 5 years ago (I am adding it more for other people who might look at the thread):

Last weekend we were in Montreal and visited the Biosphere museum at parc Jean Drapeau on Isle St. Helene. This is the second time we have visited the museum since it opened in 1995 It is built inside the biosphere (geodesic dome) designed by Buckminster Fuller for the American pavilion at the 1967 Expo.

the main part of the museum has environmental exhibits including a big permanent exhibit on the St. Lawrence.
There are lots of interactive exhibits good for kids.
Last but not least it is fascinating to see the biosphere itself and there are great views of the city from viewing platforms.

this museum seldom appears on people's lists of things to do in Montreal so I thought I would mention/recommend it. It is easily reachable by Metro.
http://biosphere.ec.gc.ca/

All your suggestions and info are great and I know they will help to make it a wonderful trip.

Yesterday I was talking to a friend who is going to Montreal next weekend and we both talked for a while about how much we love the city. I think my husband and I will have to plan a trip in August.

We had meant to try one of the brew pubs when we were there earlier this year but didn't manage to fit it in. I have noted this thread which you may already have seen
http://www.fodors.com/community/canada/montreal-brewpubs.cfm

This thread has good suggestions for fairly inexpensive restaurants
http://www.fodors.com/community/canada/cheap-eats-in-montreal.cfm

You should definitely plan to try some Montreal bagels--very different from NY. (St. Viateur or Fairmont bakeries)

Since it's summer I will also suggest Le Glacier Bilboquet for excellent ice cream and sorbets. There are different branches around the city including one in the Plateau. I think they also have kiosks in Old Montreal in the summer. we have gone to the branch in Outremont which is an attractive neighborhood with good restaurants especially along rue Bernard.

I'll check out the sites you listed - and we're definitely up for some comparison bagels! If you and your husband are there between Aug. 11 and 15, touch base - we'll meet at one of the pubs or restaurants!

I love the old port and old Montreal! There is so much to see during the day and evening. Crescent street and the downtown museums. The jazz restaurants, like modavie and upstairs are wonderful places to be. The firework competions at the old port and cirque du soliel are fantastic. So much to do and see!

Oh and ii noticed someone mentioned ice cream, if you want god ice cream try Roberto's the best Italian ice cream!