W-RPG - Western rpg, this is the likes of Obvlivion
J-RPG - Japan(or japanese) rpg , this is the likes of Dragon Quest
i prefer J-RPG, even though they are some times a bit over the top and other times oddly erotic (dragon quest girls always have big tits that defy the laws of gravity

also the storys, w-rpg's never focus on the main story and always focus on the free-roam "do what you want" aspect of the game, witch again is kool but its not gripping enough for me, i like storylines, twists, live story's, betrayals ect. in my rpg's since your suppose to be role playing, i like to have more focus on the characters than on the 30,000 acre forest that has 3 monsters to fight (again oblivion lol)
i also prefer the battle systems commonly used in J-rpgs as they are more strategic then any w-rpg ive played.
not that w-rpg are bad, hell obvlivion is a gaming masterpeice and i enjoyed the 30 hours i put in to it before chucking it, i just prefer J-rpg's lol