That is the only substantial difference, the eclipse has rear windows and the trim button is on the stick. Other than that it is the same airplane.The Katana is the older version with a Rotax 912 with a constant-speed prop. The Eclipse is newer, has a Continental IO-240 with a fixed-pitch prop. There are probably a few other differences, but that's the big one.
I will have to disagree on the spin recovery in a DA20. Its almost not fun how easily they recover.I'd probably start in the 152 to learn the basics. Its a more forgiving airframe in my opinion when it comes to stalls and spin recovery. I would solo in the 152 then maybe switch over to the DA-20. I started my PPL in a DA40, then transitioned to a 172. I found the 172 to be a better aircraft for learning basic stick and rudder skills, crosswind landing technique etc. But the Da-40 was a blast to fly, same with the Da-20.
Is the DA-20 available with the G1000?you don't need all that glass cockpit garbage when you are doing your ppl anyway.
Is the DA-20 available with the G1000?