Yes it is right the South of France is quite expensive but we are talking about the "cote d azur" it means the South East as Cannes, Nice, St tropez etc….. But if you like to be near by the mideterranean sea there is some places where it is still possible to find some very good deals and some properties which are still possible to renovate.  Montpellier in Languedoc-Roussillon is very nice and good for investment. this is a region where you are not going to find the same kind of population than in Cannes or Nice. It s far less expensive and you can find many activities for the kids. It s only 3 hours away from Barcelona by car and 3 hours from Paris by Train.
If you don t mind about the mediterranean sea you can find near Bordeaux amazing deals with many properties to renovate.
If you want more informations check my website http://www.ecaconnection.com 
I m french and i help people who would like to acquire properties in France.
You don t have to speak the language to stay in France but obviously it is easier if you could. There are many english people who lives a bit everywhere in the country and more and more french can speak English so it is not a problem.