I'm downloading all five seasons anyway. If it hasn't grabbed me by the end of season one, I'll probably stop.
If you want to try Fargo, there is no need to see any of the other seasons or the original movie. Each season has no bearing on the other. They are only connected inasmuch as they are all true stories and they all took place in Minnesota.'
'True' can also be used to mean the truth that someone involved believed, no matter how insane it may sound to some of us.
But it's a great show. I would recommend season 1 or the current season 5 if you fancy giving it a go.