psp

is there a similar system for the psp like the winrar for the ds??????

WinRAR files can contain more than just DS files. So if you want to compress a PSP file then you can easily do that with WinRAR.If you downloaded a PSP ISO and you don't know how to extract it then we'll need to know the file extension.

we have the r4 for the ds, is there something you can get that is similar for the psp.???

no, PSPs need their firmware modifying, and then you can use a memory stick to store and run games.