C152 All the way.
Definitly Cessna has the best training aircraft I've ever flown. I can't talk about the DA40 because I've never flown it, but I've flown PA-38 and C152, and trust me that the 152 is the best trainer you can get. Every airline/biz/recreational pilot says that.
Of course de DA40 is new and has glass cockpit and all that stuff, but It's better to start with the classic C152 and then jump to a brand new aircraft.
Just my opinion. Or you can wait and get your PPL in a C162. (Kidding)
P.S. The C162 is the new version of the C152, just in case.