The only version of Águas De Março worth having is the original Antonio Carlos Jobim version. Maybe the Getz version, though I confess I've never heard it. Written by one of the greatest musicians of last century. If you're interested in Bossanova:
Stan Getz/Joao Gilberto
Stan Getz/Charlie Byrd Parker
Joao Gilberto (the finest male voice that has ever sung, so far as I'm concerned)
Antonio Carlos Jobim (basically wrote 3/4 of all the famous bossa songs)
Caetano Veloso
Bebel Gilberto
Cibelle
Ellis Regina
That's a pretty good starter list...There is also an english version of Águas De Março on an album called "Jobim," though it's not really a good album otherwise.