hi need the help from u bros to find about 3.XX further upgrades:)

well hi all memmbers
i just need 1 help from u guys:)well i have not touched my psp for long time after geeting my new console but last night i was willin to play games on my psp after long time .
well before when i was use to play games in psp i did add firmare until 2.71 in DH folder which i was use to change by devhook but my real psp firware is 1.50:)
last night i found that we can play ps1 games on psp too so was happy to get some for it but now i m not able to run any of them as as totally lost:( so wanna ask that do i need to upgrade to any firmware i mean do i have to change my firmaware of psp from 1.5 to any other 3.o ea or somthing else or i can run the games by changing firmware by dev ...
welll i have no idea so do let me know as have not used any other firmaware after 2.71 i mean no use of 2.71 further upgrades thansk hops u guys know what ui mean as englsih is not perfect for me to write :(

yes you need to upgrade to 3.02 OE or 3.03 OE. but if you do, dont worry, you can go back to 1.50 at any time you want to from that firmware