What is a good PSP Emulator for the computer?

[Meganarcle]

What is a good PSP Emulator for the computer?

[Zekro]

For now jpcsp is the best psp emulator

[EvilSR]

Try ppsspp:
http://www.ppsspp.org/downloads.html

[Sarisa81]

PPSSPP is really fast when it works, but since it's so new it's not very stable in any sense; sound quits working from rev to rev and games crash for strange reasons (e.g. in the current revs Dissidia 012 crashes on autosave if your save file is either encrypted or unencrypted, and which causes a crash differs copy to copy). You'll probably need an external program to use a gamepad; I recommend XPAdder.

JPCSP is slow unless you've got a decent CPU and a better-than-average graphics card, and it's prone to graphical glitches nonetheless, but being more mature it's more likely to work and work reliably.

I hate to say it, but you should choose based on the game(s) you want to play - if one simply won't run the game you're stuck with the other - your specs, and your tolerance for things abruptly breaking.