Chrono Cross is, at least in my opinion, the best of the games you're looking for. By far.

As to FFX-2 vs. FFTA, if the system requirements (PS2 vs. GBA) aren't an issue, then it essentially comes down to what type of game you prefer. I know that a thread exists in the FFTA section addressing this question, so I'll leave it up to you. I'd recommend both, but do as you see fit.

But get CC. It's amazing.