Everyone has different needs and expectations. Here are mine. First, for two couples with a 2-year old child, you likely have diverse needs and a schedule that is going to be dictated largely by the child. That also says to me that privacy and space would be desirable. For both, I really recommend a condo (2 bedrooms with 2 baths are fairly common at Tremblant). A condo would have a kitchen, which also is very convenient and, maybe best of all, a place for the 2-year old to nap and go to bed early without cramming the adults into a tiny space.
Condos do not usually have breakfast, a disadvantage. Look at Ermitage du Lac, which is in the resort village but in a quieter side. It has a nice playground and there are convenient places to walk with the 2-year old as well, yet you would be only a few minutes from the activities of the village. Ermitage also has a pool and breakfast and is just a short walk to the municipal beach, if it is open. Ermitage is well-located for a two-night stay. There are lots of other places as well, some on the mountain and some outside of the resort, so post again if Ermitage doesn't suit your taste of budget. It wasn't clear if you are looking to pay $150 to $175 per night for all 5 of you, or if that is your per couple budget.
As for activities (no hiking, canoeing or golf), there are gentle strolls around the village or on some of the trails, bike rental (you should be able to rent a child carrier-equipped bike), tennis, sight-seeing, gondola rides to the summit and touring some of the nearby villages. There are swimming pools and there also is a tourist boat on Lac Tremblant (it holds maybe 60 passengers). The 2-year old probably would enjoy all of these in moderation (except tennis) and there also is a little waterfall near the marina, just outside of the resort village. In the resor t village, there is a pond with kiddie rides. There are good supermarkets in St-Jovite, which you will pass through on your way to the resort. It is about 10 minutes drive away.
