i have a powerbook g4 that is currently running osx leopard 10.5.4 i think. It has a password that i apparently forgot and the password hint i set is completely useless. i have tried booting from my retail leopard osx disc by pressing c when the powerbook turns on and that has not worked. it fails to boot up for some reason. also used a tiger dvd to see if that would work. failed as well. i've also tried entering single user mode, but that fails. i also think i tried pressing the option button when it starts and that failed. at one point i got a screen with an arrow and a blank text field and lock icon. what exactly is that? any tips on troubleshooting this further? This has been very frustrating.