Rocket French is the standout winner in my opinion. It combines both audio lessons with interactive computer games. Strangely enough, it is also the cheapest option. Fortunately, this is one case where "you get what you pay for" simply doesn't hold true.
The audio lessons really focus on building your ability to actually speak the language and they do it in a way that's both interesting and efficient. There's no learning useless, boring phrases here.
The computer games also make it a fun and easy way to build vocabulary, learn your verbs and improve your verbal recognition skills.
Of course, for those of you who just love grammar, there is plenty of information regarding some of the more technical aspects of French.
I really can't recommend Rocket French any stronger, if you want to take your French to the next level, then go check out the site today.