Which do you prefer and why?

Doesn't really matter.  This game's been redone numerous times.  Just go with whatever set of graphics grabs your fancy.

It looks like the gameplay is pretty different for the two. Knizia can be good (sometimes). I dunno. I'll probably buy if it goes on sale again.

I got the impression that they have different rules as well... any other comments about a preference?

"The Legend" game and "The  Movie" game have different rules as they are completely different games.

"The Legend" is a game of risk management and hand (of cards) management, main mechanism is auction and players bid to gain choice of benefits and prevent losses.

"The Movie" is a remade of the game called "Kingdom", with more special function tiles.  It is a mathematical game, main mechanism is tile placing and scoring by your pieces (sounds like Carcarsonne but they are actually quite different).

Both games are entertaining, but your personal tastes will probably cause you to prefer one to the other.  I'll definitely recommend you read the rules first to decide which game you'd like, because there is no way to compare which one is "better".