I don't know if I'd call FF7 the most suggestive, I would have said the costuming in FFX2 was more suggestive. However, FF7 is certainly a good place to start them off on the series (plus it has some of the Kingdom Hearts characters). FFX2 isn't a lot of fun unless you played and obsessed over FFX (which is probably the best game of the whole series), but it's basically about 3 teenaged girls running around and having "girl power" adventures. FF8 is okay, and definitely has some of the Kingdom Hearts people in it. FF9...well DH didn't really like this one, and I had trouble staying awake to watch it. FFTactics is more my style, but it's not exactly a rpg.
Now, other suggestions for young-ish girls:
Harvest Moon (this series is by far the most addictive game I have ever played and it is 100% geared towards girls)
Chrono Trigger/Chrono Cross
Zelda (I personally like Windwaker best, but they're all pretty good)
O Kami
Pikmin (not a rpg, but awesome)
Katamari (also not a rpg, but even more awesome)