For those who regret upgrading their firmware to 2.0 then here is the downgrader.
http://forums.qj.net/showthread.php?p=177883#post177883
I downgraded my psp from 2.0 to 1.5 and it worked! The reason why you want 1.5 over 2.0 is because of the homebrews (emulators, cool programs, they got mac OS running on PSP LOL)
Also, use this version of 1.5 ( http://files.pspupdates.qj.net/cgi-bin/ ... ,0,40,1410 ) as the one that was posted there is japanese.
yay