Rather than just do as requested (list my favorite Redford film), I'll buck the system and drop my favorite Redford STORY on all of you:
When I was in film school, one of my buddies came to class one day and told me how 'something very strange' had happened to him...
My friend had been sitting in his house when he noticed that some 'weird guy' was sitting in his car across the street just STARING at my friend's house.
The weird guy sat there for hours... simply STARING.
My friend started to get wigged, and began thinking about calling the police, when the weird guy got out of his car and approached my friend's front door.
Crazy as it seems, my buddy decided to answer the weird guy's knock at the door.
The weird guy seemed pretty nice, and explained to my friend that he lived in this same house as a kid... and kindly asked my friend to please check the attic for an old steamer trunk. The weird guy went on to say that he hoped it might contain his little league uniform. With that, the weird guy left a phone number and drove away.
My friend, of course, hightailed it to the attic... and, sure enough, found the trunk along with the uniform... photos... and other mementos from this guy's childhood.
You've probably figured-out that the 'weird guy' was Redford... and my buddy was a young Michael Bay (VERY pre-Armageddon). Weird world, huh?
One other twist: I told this story years later to another friend, Richard Schickel (film critic for TIME magazine), who is very close to Redford and his family. Schickel told me upon hearing this story that he had a similar experience when he visited the Redford home in Sundance: on Redford's mantle were some old tin toys.
Schickel asked why an old toy held such a prominent position. Redford explained that he visited his grandparents old home in the SF Valley (I guess Redford went thru a reflective period of visiting old homesteads??), and surprised the current (elderly) owners when he graced THEIR portal.
When he shared some old memories of playing with his toy cars in his grandparent's backyard, the old couple's eye's lit up, and they dragged him around to their garage. There, on a shelf, was a tin car covered in dust and cobwebs. Redford instantly recognized it as being one of his old toys.
And that's... the rest of the story.