Guilty Gear X2 has the best damn tunes there is...On the Neo-Geo, it has to be in Garou (Rock's stage especially). The dude who did the music for Garou must have been listening Robert Miles' Children over and over again when he composed Rock's music.
It's a good thing that you're taking interest in this. I'm not so much into compiling my own emulator, but there are lots of people out there who need a guide like this. I hope it turns out good.
You're trying to play it from disc 2 or something...That, or then the disc has somekind of a protection. Some CD burning software can bypass certain CD protections. Or...Create an ISO from the CD and mount it using Daemon Tools, then try to play it.