FFX is pretty solid; it was the videogame my parents got me with my PS2. Good battle system, overall decent characters (even if I didn't like the leads), and a great plot.
FFX-2... the battle system's probably the fastest-paced in the series thus far, the newer characters are intriguing and the costumes are pretty. Otherwise? The returning characters all got a lobotomy, the plot is crap, and continuity is absolute bullshit (one character goes from sweet little kid to teenager in TWO YEARS).