Which of these games should I play?

Mass Effect

Grand Theft Auto IV: Episodes from liberty city. (played original)

Dragon Age:Origins

I can only choose one, which one should it be?

Use the sticky at the top of the forum

Dragon Age. Mass Effect 2 is coming very soon and EFLC isn't worth the money, because you can rent it and beat it in 15 hours. Get Dragon Age.

Mass Effect if you like sci-fi and epic awesomeness.