AdriPSX is the bets psx emulator you can use if you have a lower-end system, and it's code is very tight, small, and no fancy extras. no plugins either http://adripsx.psxemu.com/
but if you have a decent computer, epsxe is probably the best
If you have a decent computer, I'd say epsxe. Plays all my old school final fantasies at wonderful speed, great graphics, great sound. The only problem I've ever had is if you load a corrupted iso, one of my ffix iso's is corrupted i think, some of the fmvs play funny but when i used a different one it played fine.
I got psxfin exe on,Although i have used epsxe.I didn't have any problems with epsxe except the fact that i had some pretty funky sound errors with games like resident evil 3 in which the game skipped and froze on me.It could be that i didn't program it right or that the game works better on psxfin
