The
Godfather DVD Collection page has a link for more info about the Godfather in "widescreen", as explained to me by Harlan Lebo:
"For The Godfather, Willis shot it in full 35 mm frame -- roughly 4:3 ratio. Gordie knew the film would be cropped down to fit wide screen theaters at around 1.85:1, and planned accordingly...."
GF2 was filmed in 1.85:1 aspect ratio.
As for GF3, it was "was filmed at an aspect ratio of roughly 1.66:1, and then cropped to the wider 1.85:1" according to
this review of the laser disc version.
I'm starting to get a headache

What's all this mean? Check out this
DVD FAQ for details...
JG