Finish Chrono Trigger. It's the best game ever. Then go play Chrono Cross. While there were definitely WAAAAAY too many characters, it's still quite good. True, the battle theme wasn't that great, but every single other peice of music in the game is excellent. Especially Kid's theme, the music in Chronopolis, and the end theme. But definitely finish Chrono Trigger first - then play Chrono Cross to find out how everything you did in Chrono Trigger shaped what would happen in the new future.