oblivion all the way, two worlds is an amazing game, but oblivion was just way more funner i'd have to say. my oblivion character dominated. i am level 46 redguard. i use mostly ebony armor, with any type of strong enchated weapon. mostly swords of bows. no blunt haha.
oblivion was a truly fantastic game that took tons of time to make, two worlds on the other hand had horrible production value, the worst voice acting ive ever heard and very unbalanced combat. i had fun with both but i took two worlds back after I beat it, oblivion I still play.
I turned in Two Worlds right after I completed it. I still own Oblivion and have no intentions on giving it away! Oblivion is by far the better of the two, (except for the occasional freeze).