If your going to listen to get to know Serge Gainsbourg, listen to this album. There's so many wonderful songs of this one:
Cannabis
Initials B.B.
Je T'aime Moi Non Plus (ft. Jane Birkin)
Qui Est in Qui Out
Bonnie and Clyde
Sea Sex And Sun (via Amazon)

I love Serge Gainsbourg! He's Beck meets Frank Sinantra, but with that French mystique.