Well, of course, compared to the graphics in FF X, those of FF VII, or even FF VIII cannot begin to compare (what's gonna be fun is for those who will start with FF XIII and will have to go all the way back to FF VII - their eyes might hurt a lot ). I remember though that when I got FF VIII, at the time of its release, everyone was in complete awe (especially since FF VIII had the first really amazing-looking CG scenes with pretty realistic characters).

Nostalgia apart, buy both, but I agree that the transition will be a little easier on you if you start with FF VIII. That being said, both FF VII and FF VIII have gaming systems which are widely different from both the previous and the following FF (FF IX was a kind of step back in that regard), so it may take a little time to get used to it.

Oh, and once you've played them, try FF VI, which still remains the most gratifying FF, IMO (although FF XII arrives dangerously on its heels now )