[Help] PSP or DS - but in other way

So emulating PSX or N64 on the first Xbox isn't a perfect idea. What about running PSX games on the PSP. Go or no go? So I do have a few questions (I've been living in the cave for about two years - please help me and don't made me use the Google )

1. Do all the PSX games work on PSP?
2. What do I need to run the games (in short)?
3. Can any PSP "version/model" actually do that?
4. Can any PSP model be plugged into the TV?
5. What other consoles can the PSP emulate and what about Dos games ports (I've heard about Duke Nukem 3D)?

And finally:

6. What can the DS do (emulating some consoles or some Dos games ports)?
I've seen Duke Nukem 64 on DS (screenshot). I am sure DS is too weak to emulate N64. So was it a hoax or remake?

Thanks you in advance...

Jam it back in, in the dark.

Guys. You have helped me BIG time. Thanks.

So it seems that I have to buy PSP 2000. But why do I need to change the firmware if the "PS games running capability" is built-in by Sony? And can I reach the point of no return while swapping firmwares (vide KrelEN's words about downgradable firmware)? And is PSP region free (PSP games)? And for last: will the GBA NTSC-US games work on European PAL console?

There's nowhere I can't reach.

That's why I am asking, because there was no word about PSP being region free on the Wikipedia :P

Thanks again.

BTW Soluzar, you seem to know everything about homebrew for ANY console (your advices on Max Evo for PS2 were priceless two years ago).

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