That depends on what OS you're running. If you're running XP, then it's Pete's OpenGL2 by far. Otherwise, I'd stick with Pete's OpenGL. For sound I'd use Eternal SPU plugin (the built in epsxe one is pretty good to, though), and the built in cd plugin.
If you're considering using filters and shaders and whatnot, there's an excellent racketboy article here: http://www.racketboy.com/retro/sony/ps1 ... tings.html
