I take it that there are back ups copies your trying to play? I have back ups of both of those games and they work flawlessly. What media are you using? What software are you using to burn it? Speed?
Am using a modchip. Try better media like Verbatim, Taiyo Yuden, or Ritek. I used Ritek G05's for X2 and it plays flawlessly. FF games are very heavy on videos so you need to use good quality media. Secondly, have a look on swapmagic fix.com, there may be a patch for those games or you may have to use a CDloader.
i backed up FFX - works fine. I used dvddycriptor, to make to iso. then used Nero to burn at 2x on a verbatim dvd-. it doesnt need rebuilding or anything.