Need help with i book

Ok this is my 1st post I have been given a I book to fix. Not having used 1 before ( been a windows user switched to Ubuntu just over a year) I need to boot this laptop up. It loads the apple logo then what looks like kernel panic then the last line reads Panic We are hanging here Hope someone can help

Ok an update maybe some one can help, I have tried booting off of a known good ubuntu cd several in fact if the hard drive is faulty should I still be able to run off a Live cd?, also if I hold down the option button it loads with 3 icons left 1 is a U bent arrow centre shows a Hard drive with a blue cross (hence faulty hdd) the right icon shows an arrow pointing right. Hope I can receive some help plz

More than likely if it's kernel panicing right at startup, it's bad RAM. Try replacing that if you have some extra just to see if that works.

Unfortunatly I dont have any regarding the 3 Icons what do they do I cant switch to any, The icon with the crossed hdd seems the only one when hitting enter takes me back to the kernel

No clue, I don't really use Linux, and definitely don't use it on a Mac.

But it sounds like bad hardware, most likely RAM.