They're a lot like Chrono Trigger in gameplay.. turn based, characters can join together to form combos, and you don't stay stationary like FFIV through X but actually move around as you do actions (not on your own).
Anyway, it has heavy themes and myths from Japanese culture, I believe, and is a dark story to boot. Great characters, off the wall humor, dark tone, great gameplay and a hell of a great story.
The original Shadow Hearts goes into Shadow Hearts: Covenant, then SH: From the New World is like a side story told with a new cast of characters. Anyway, SH and SH:C are probably the best, with Covenant being the absolute best in series.. though FtNW is nothing to pass up, either.. then again, that's just my opinion.
They're a great trilogy of games, though.. and some of the best RPGs I've ever played.
That's about all I'd be able to recommend along with Rogue Galaxy (action RPG by Level 5, great company), Dragon Quest VII (totally old school RPG also by Level 5 in conjunction with Enix) and Final Fantasy XII (best RPG I've ever played on the PS2).