Yes, svsg, that's the ending sequence that was masterful: Michael slumping down in a chair in the boathouse after the shot that killed Fredo rang out; then the flashback scene of a younger Corleone family, striking the viewer with the fact that half the people in it are now dead; then as that scene fades, Michael's brooding face and downcast eyes as he sits alone, the autumn leaves swirling on the ground. The audience can practically taste the winter in the air and can feel the winter in Michael's soul.
This entire image weighs heavily in my mind when I view it. It holds so many complexities. A wistful nostalgia and a longing to turn back the march of tragic events echoes in each frame. The irony of the audience being able to see what Michael could not -- the blurring of his moral boundaries and the extent to which his psyche has been diseased by not being able to trust a single soul -- all underscore the regret and self-destruction inherent in the "business he's chosen." It is one of the most memorable and devastating of movie endings.
This is just my own opinion, mind you, but the ending of GF III is amateurish in comparison. Mary dies, Michael has some flashbacks, and then Michael keels over almost laughably -- like a Charlie Chaplin figure in a silent film. Yes, I felt sad when I first saw it; but I also felt manipulated. This ending blatantly tried to recreate the tragic portrait at the end of GF II, but without the subtlety or complexity ... just a visceral claw at the emotions. The GF II ending, flowing naturally from character and behaviour, appealed to the heart AND to the mind. The GF III ending, by comparison, is an appeal to the tear ducts.
At the end of GF II, we saw a shred of Michael that realized just how evil he had become. And that final shock -- that some things were irredeemable, that he could not resurrect his brother, that he would never know the face of his unborn child, that the murder of Carlo would never bring back Sonny -- was part of the kicker. At the end of GF III, I got the feeling that he should have known all that by now; he no longer seemed a tragic figure, but a slow learner who bumblingly lost his daughter more to a freak accident than to his life of crime, which he was trying to get out of.
In my view, GF III was a mistake that should have never been made. How could the filmmakers have possibly expected to top the superior ending of GF II? GF II was the perfect tragedy; it was Shakespearean ... and it should have been the end of the story. GF III dilutes the impact. We see Michael in Part III reconciled with his children, on civil terms with his ex-wife, being awarded for his charity work, etc. It's all too pat, almost as if the horrors of Part II had never happened.
I don't know about others, but when I see Michael confess his sins in Part III, the sum effect for me falls far short of what I imagined the torture in his soul must have been like at the end of Part II. By spelling it all out, Part III ruins Michael's future for me. I thought it was better kept in my imagination.
Verdict: GF II ending far more tragic, memorable, and a superior piece of film making. GF III should never have been made; it's too hard to follow up two masterpieces.