There are actually 3 version of this movie, I have not seen any of them!
Oldboy (2003) -http://www.youtube.com/watch?v=2HkjrJ6IK5E
Bollywood was first to remake Old Boy
Zinda (2006) -http://www.youtube.com/watch?v=Pmyi4Ti2owg
Oldboy (2013)-http://www.youtube.com/watch?v=Vd20pywMXuY
I am actually thinking of watch Bollywood one first before US remake, then US remake won't seem so bad compared to the original