In Bordeaux it's better to use public transportation if you are in the centre. The company in charge made special fares for people, based on their age, and status. I do have my driver licence, but I don't own a car there, anyway we need a parking place, and it's difficult to have one there because there are still a lot of cars and not enough place to park.
Recently they set up bicycles like in Paris : there are several stations where you can take a bicycle, and use it for an hour or the entire day depending on the subscription we made. It becomes handy when we have short distances to make, but if the station we are going to is full, we have to turn back to another station to put back the bicycle
There aren't any subways there, but I think it's not that bad. I read an article about the polluted air in subways station and it is indeed worrying. The particles made by the subway car and wheels remain suspended in the air, because the air isn't renewed, and the pollution reaches its peak when there are a lot of people with the more frequented station. In the long term it can cause serious diseases as well as lung cancer and such.
However the advantage of the subway is its speed and the reduced waiting time compared to the bus, and nowadays everyone is always in a hurry. I am even amazed at myself for being so stressed out at the time, and I often get really upset when waiting for a bus to come for 15 minutes, when they are supposed to be there more often. It's the same when I often see 2 of the same bus line passing one after the other : the drivers don't respect their timetables at all.