Brewology

I am looking to buy a psp, a used one is okay so I have options on what firmware I can buy. my knowledge of homebrew is limmited at best and I am having trouble figuring out what homebrew can do what, or if they are all basically the same. I would like to be able to play psx, snes, gba and if possible, ps2 while still being able to play regular psp games (I understand some of them require updates to the psp?) So, I guess the appropriate questions are:
what firmware should I try to get?
What Homebrew should I use?
is there a link you can provide that will tell me what type of game (rom, iso...)(I am very new to this) to load onto it and how?
and (this might be a very dumb question) what do you do about games that would use a right analog stick?

thank you for your time effort and help
anoddmind

I have a fat psp that is currently at 3.90 M33 custom firmware. I am selling it along with the power supply and battery. I also have a 1 GB memory stick if you are interested. The memory stick will be needed if you want to load homebrew or iso's on it. If you were to buy mine I would load a little bit of everything on there for you so you can see what goes where. Let me know if you are interested.

how much is it?

I am asking $150 for the PSP, $20 for the memory stick and $10 for priority shipping. I will of course include the battery and power cord.