question about the psp

[mjohn15]

I plan to get a PSP when it comes out and i read about the memory stick things and how you can get a a 4gb stick for it so could i play my emulators and roms on there if i put them on the stick and will there be away i can back up my psp games using those mini disks they sell i mean will i need it modded i know some people already got the psp from japan.i mean it would be pretty sweat if i could play old snes roms and sega roms on my psp