If you're using ePSXe, try to use these plugins below :
Graphic :
Pete's OpenGL2 (set it on 'Nice' found in the configuration)
Sound :
Eternal SPU plugin.
Please note that you need to have a better PC specs to make it better. Also you can dump the CD into a image file using
ISOProducer (or other CD imaging software) and mount it with
Daemon-Tools.
If problem haven't been solved, try to use other emulators like pSX or Xebra.