yes you can,
1) to play only (iso/cso) gsmes "games made for PSP & ripped from it's original UMD", you'll need only DevHook.
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2) to play all Homebrew games & apps "games made in PSP games format by hoppy programmers" You'll need to downgrade your PSP to fw 1.5,
the last option will need some research from you
1) check your motherboard type, by oppening your UMD Drive & viewing the number in it, if it's on your left, you're fine. but if it's on your right & it reads IC1003 then you have the god damn TA-082 Motherboard that bricked my psp & i wouldn't recommend you downgrade it on your own.
Hope That helped.