PowerBook wont start up

[silver10]

In the last few hours I've had 3 "Kernel Panics", but after turning it off the 3rd time, I got stuck when I started it up. It just hangs on the blue screen where normally the box that tells you its loading comes up.

I tried starting it in Safe Mode, but it does exactly the same thing.

PowerBook G4 12"; OS X.3.4; 768MB RAM

 

[immdb]

Start up from the Mac OS X Install Disk by inserting the disk and restarting your computer holding down the C key.
Choose Installer>Open Disk Utility and select the disk in the left column.
Click First Aid.
Click Repair Permissions.