Which French colonies are you thinking of, exactly? Yes, the Louisiana Territory, perhaps part of Canada, though I'm not sure how much colonizing was actually done in these territories. But having half of South America is quite a feat as well. I guess when I think of comparing colonies, comparing the size of the colonizing nations is in order. For a city-state like Venice to control trade in the eastern Mediterranean for hundreds of years is more impressive, in my mind, than had Spain been able to do this.
Now that I think of it, how are you defining success here? All the nations - France, Britain, Portugal, etc. lost their holdings eventually. Britain had control over America for less than 200 years. Could success be defined by the nation that earns the most income per capita through its colonies?