hello. I have played through chrono cross on pcsxbox so i know the game is fully playable. It will work fine with the default settings, but i think i turned off frame limit to make it run a little bit faster. The battles may still be a little slow sometimes.
I didn't find a way to swap discs in pcsxbox so at the end of disc1 i had to save to the memcard file.. FTP the memcard.mcd to my pc and complete the discswap in epsxe, save and transfer the memcard.mcd file back to the xbox.

Good luck