How can you ask such a cruel question?!
I'm french, I love singing and I've heard Charles Aznavour et Edith Piaf since a very young age. No matter how long I would think about it I don't think I could ever pick one over the other...
However, I can tell you the two songs I like the best! "La bohème" from Charles Aznavour. The music is quite unique and the lyrics are so rich. It is such a colourful story! Charles Aznavour sings very fast while managing to keep a clear pronunciation. It is quite a challenge to learn the lyrics of this song, but when you do, man, what a pleasure !
My favourite song from Edith Piaf might be "Hymne à l'amour", because it is one of the most beautiful love song ever...
It is a great idea to learn french with music! That's what I did to learn english, starting from a very young age. It helped me tremendously.
Thanks all of you guys i know is a hard question that's why it's asked ;)
Vamos, la idea es que se mojen!