You would get worse results recording from an emulator than using the dedicated movie ripping program "jpsxdec".
When using jpsxdec, you are still at the mercy of the low resolution PSX versions (320*224), which also used a crappy codec that left a ton of noise and compression artifacts. Seriously, it's REALLY bad. So bad, it hurts.
The Toshiba DVD has its own thread around here somewhere on Qhimms. The videos on it (incomplete list) are from a higher resolution render (640*448). Unfortunately, the DVD uses interlacing, and has introduced other nasty artifacts. But even through this, the result is far better than the PSX versions once they are cleaned up, and the awful colour has been corrected.
It's a tiny glimpse of what might have been.
If Square had bothered to think forward, they would have backed all their data up, and rendered everything in a few resolutions. They didn't. Once FF7 was complete, they basically just dismantled everything and then years later said "shit."