Here is a small guide for what emulator is best for whatever computer you have in your possession on any given day:
Pentium 200 with Voodoo 2 (Corn, SupraHle)
A Pentium 3 or 4 750mhz (sic) (Any, Pj64, 1964 and Nemu esp)
And now an AMD K62-500 with Voodoo 2 (Corn, SupraHle)
At the end of the day why not download all the emulators and see which one fits your need the most - the files are miniscule (even on a slow modem such as I am on).