The main tourist spot in Old Quebec City lies at the foot of the Chateau Frontenac within the old city. There you will find alleys with high scale restaurants and other touristic displays and stores. The lower city area know as the Petit Champlain, which is absolutely beautiful, has however been "Disneyfied" and filled with tourists and high-scaled stores. This leaves most of that area as an architectural must-see but without any real cultural life. There are also many cruise ships bringing in people during summer months.
Since the old Quebec City part within the fortress is fairly small, it is unfortunately difficult to get any original feel due to the amount of tourism during summer and nice weather week-ends.