A typical JRPG is the little kid/teenager ends up saving the world from destruction. Party members consist of the stereotypical ditzy girl, loner, and token "old" guy (anyone 20+ years old). It's basically the same old story re-told a few hundred times.
Now I'm not saying WRPG storylines are all that original either, but at least the majority (if not all) don't revolve around the protagonist being jail bait. Dragon Age is my favorite WRPG. My favorite JRPG will always be Suikoden II.