The movie I most associate with James Caan, and IMO one of the best he made, was Brian's Song...
Brian's Song (1971)
CREDIT: EVERETT COLLECTION
Caan earned his only Emmy nomination for this TV movie, a true story about Chicago Bears football player Brian Piccolo (Caan), stricken with terminal cancer after finally turning pro. An ABC Movie of the Week, it chronicles Piccolo's friendship with teammate Gale Sayers (Billy Dee Williams) as the first interracial roommates in the history of the NFL. The athletic Caan had to actively be told to slow down while filming football scenes with Williams, whose character was renowned for his speed on the field. But it's Caan's dramatic acting that really shines, catapulting the project to such success, it vaulted from the small screen to a theatrical release. It's still one of the most dependable movies for making men cry.
He was a very likeable character playing Brian Piccolo.. and that's the way I always think of him.
Contrary to this, I took an almost immediate 'dislike' of his son (Scott?, also an actor) and I can't tell you what role that stems from, but I generally don't even watch programs that he's in...