Well Lost Odyssey is a must buy. Best JRPG in years and best of this generation. Remember when Final Fantasy titles didn't suck? Lost Odyssey captures the feel of the Final Fantasy franchise back when it was at the pinnacle of the JRPG genre. Sakaguchi hit one out of the park with this game. Excellent characters, story, voice acting, and battle system (provided you don't mind turn based battles).
Eternal Sonata was disappointing to me. I loved the battle system and the art style but other than that the game was lacking. Its short, the story is weak, and there are virtually no side quest outside of one music sidequest. I like the unique idea behind it and it was great to learn about Chopin but the actually story for game was beyond weak. I won't spoil the story, but Crescendo did something so stupid I nearly stopped playing the game.
Blue Dragon is a game you should rent first. I enjoyed Blue Dragon but some people out right hate it. It is also turned based but it doesn't have random battles. Blue Dragon is more of the classic "kids save the world" type of JRPG. My main problem with Blue Dragon is that it was extremely easy. Actually both it and Eternal Sonata were ridiculously easy.
Enchanted Arms is was fun for me as well. The english voice acting was awful but I liked the battle system. The grid system and different ranges for you attacks made it a unique take on the turned based system. The story isn't exactly epic but it is better than Eternal Sonata's IMO. It isn't full of side quest either except for the insanely long bonus dungeon. You should be able to pick this game up on the cheap given its age.
I will give you this advice though. If you play Lost Odyssey before any of the other RPGs it will make them seem much worse. Its the only "AAA" JRPG available for current gen consoles. The others titles are C- to B in quality IMO.
