I don't know if this is your problem but the games mentioned Square had some problems with, they weren't right from beginning. Freezing was one of the problems. Square fixed this in the later batches.
I had trouble with Squares FF trilogies and Chrono cross which also suffered a freezing problem.
Like I said, don't know if this is what your running into but it might be.
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Actually I do have to some what agree with this although it's little off from the topic..While back I heard that FF Anthology doesn't seem to run too well on the PS2 but it works fine on Ver.1 when I had it..So I guess Sony had a Recall on some PS2 and square did a recall as well perhaps..I'm glad all the Square games I purchased works like a charm..I mean what are the odds?
You know? Why couldn't this type of Odds be with me or you in the lotto?We'll filthy rich..Heh..Heh..