Both tend to be linear I think, however JRPGs use (surprise) more Japanese and Asian methods of revealing character, more overt use of symbolism and metaphor, while WRPGs use Western movie methods for the most part (and often badly truth be told)- although there is an increasing trend to try and adopt emergent story-telling - which I've found wanting for the most part as it mostly means - act good and get these specific quests and result, act bad and get these specific quests and results.
Try to be reasonable... its easier than you think...