They aren't the same movie. They were made in the same year and I believe the same plot, but different actors (it was weird to me also). One of them is rated R and the other is PG-13.
I just took another look at the 2nd movie and noticed in small print that it was originally produced in 1979, so I'm guessing it's the original and the other is the 2006 remake.
I'm willing to add in 2 additional movies of winners choice if the auction goes above 2,500! The additional movies to choose from are: Lord of the Rings: The Fellowship of the Ring, Lord of the Rings: The Two Towers (BNIP), Kingdom of Heaven, 300, Pineapple Express, Lara Croft Tomb Raider, and The Others!
Just a reminder for all those of you who are watching and not bidding. I'm going to include 2 extra movies of the winners choice (from the selected list) if the auction goes over 2,500 credits!!! Only 22 hours left, let's get those bids in ladies and gentlemen!!!