What do i need to play SNES/Genesis games on my PSP?

I got a new PSP for christmas, so its probably version 2.0 or 2.5 right? (I came with the internet browser already installed if that helps).
Ive read that you can play SNES and genesis roms on a psp.
But what would i need to do this?
I know i would have to get the roms and the emulator, but what about downgrading or whatever?

Could someone tell me exactly what i need to do to play these please?

thanks x

Ok well before i can answer your question i need you to scroll all the way to the right, then down to system settings and tell me what system software that you have. Once you fine out post and i will tell u how to do that.

Ok well before i can answer your question i need you to scroll all the way to the right, then down to system settings and tell me what system software that you have. Once you fine out post and i will tell u how to do that.

Version 2.50

Ive been messing about with it a bit. And i tryed that eloader thing with GTA and uo_Snes9x. It worked once and loaded up Final Fantasy VI, but i just put some more roms on and now when i chose uo_Snes9x from the menu of the eloader the screen just goes black and then my PSP turns off.

well, there is a way to play homebrew on 2.50, but you have to have a real copy of GTA LCS. Whithout it, then you cannot play homebrew.

well, there is a way to play homebrew on 2.50, but you have to have a real copy of GTA LCS. Whithout it, then you cannot play homebrew.

Yeah I have the real GTA.
Its working now, well...now and then. It keeps going black and then turning off when i chose the SNES emulator from the eloader menu.
How do i fix this?

Well their is a new eloader that was just realesed called brown ale you can get it here http://http://dl.qj.net/eLoader-Brown-Ale-%28v0.9.5%29-Gaming-Consoles-PSP/pg/12/fid/4950/catid/114 and that should fix the problem that ur having.