I saw this movie maybe five or six years ago. The main reason I wanted to see it is because of the name Kramer. Any fan of the TV show Seinfeld can't help to think of the character when they hear the name Kramer.
The movie has a great premise. A man's wife leaves him not because he's a jerk or anything but she is unhappy with her life. Leaving with almost no notice, she turns her back on not only her husband, but their son as well.
Then he has to handle being a single father with a career. At first he struggles, as his patience vanishes when his son starts to have normal temper-tantrums. But he gets the hang of it, and really enjoys it. After about year or so, his wife returns and wants their son back. With a custody battle to follow soon after.
It actually won the Oscar for Best Picture in 1980 and I can see why. It's also neat to see Dustin Hoffman and Meryl Streep so very young in this movie.