How do you go to recovery menu in my PSP?
Completely shut down your PSP as in hold the power button up
until the screen goes black. Then hold R shoulder button then turn
your psp on. KEEP holding the R button and it should go into the
scary black Recovery menu.
Then choose what you want to do. If you have the option of
turning on the vsh then do so, to make life easier when you want to
quickly change a setting.
Also check out psp wiki:
http://alek.dark-alex.org/pspwiki/index.php/Recovery_Menu
all your problems solved :)