I agree with Mike, I think GFII is the best, there isn't much competition, GF and GFII are simply superior to all the others listed. (But I didn't see OUATIA, tho ) Even though PII is longer than GF, I enjoyed it more, since Michael was my fave character, and it did have Bobby as Vito, and it had an larger budget. I (obviously) agree with Don Pope as well; without GF there wouldn't be an GFII, but that doesn't make it better.
"I won't be a man like you." - Michael to Vito, orginal Part II ending
) Even though PII is longer than GF, I enjoyed it more, since Michael was my fave character, and it did have Bobby as Vito, and it had an larger budget. I (obviously) agree with Don Pope as well; without GF there wouldn't be an GFII, but that doesn't make it better.