My Mac PowerBook won't boot

[44-Ryan-44]

I have a mac powerbook 3.1 (400). It was in mac os x and I started it up in classic. Then I wanted to start it back up in os x but when it was booting it froze and wont do anything. What can I do?

 

[Kyomii]

Try pressing the x key on your keyboard while booting it - keep the key depressed for a good few seconds until it starts to load the OS (this may take more than one attempt.)