ePSXe is generally touted as one of the best PS1 emulators but this in my opinion is up there with it (it is certainly far easier to set up effectively), v1.11 has just been released with the most interesting change being a linux port.
readme:
v1.11 Ported to Linux
Log window keyboard controls
Added Arabic, Croation, Norwegian, Persian and Russian translations
Fixed bug in CD not usable error message dialog
DEP no longer needs to be disabled in Windows for pSX to work
Added aspect ratio correction
Centred framebuffer when it doesn't cover the entire screen
Fixed controller config dialog bug (pressing button fills all controls)
Homepage:
http://psxemulator.gazaxian.com/
Enjoy.
readme:
v1.11 Ported to Linux
Log window keyboard controls
Added Arabic, Croation, Norwegian, Persian and Russian translations
Fixed bug in CD not usable error message dialog
DEP no longer needs to be disabled in Windows for pSX to work
Added aspect ratio correction
Centred framebuffer when it doesn't cover the entire screen
Fixed controller config dialog bug (pressing button fills all controls)
Homepage:
http://psxemulator.gazaxian.com/
Enjoy.