Ibook not booting up?

So, about a week ago I was running a software update on my Ibook. I'm not sure which Ibook it is. It's not the clamshell one. I think it's a g4. Anyway, after about an hour I realized that it had frozen. I held the power button down and tried rebooting. I go to turn it back on and all I get is the apple logo screen with that spinning wheel. I waited it out and after about 30 minutes I gave up. I've been searching high and low for an answer. I did the fsck -y thing and it said the HD was fine. I don't know how to fix this. Help?
I've attached a picture of what screen it stays on.

Will the iBook start in Target mode - hold down T key after powering on. If it will do that then download the combo updater using the computer u used to write this, then connect it to the iBook in Target mode with a firewire cable and install the combo update on its HD. If that method is not possible then others may have a better idea.

I decided I'm going to just try to re-install tiger. Probably won't work, but it's worth a try. If anyone has any other suggestions, please post.

HI I am having the same trouble with an iBook G4 800mhz. I can get into OSX in safe mode by holding the shift key down , but when i try to boot normally or even reinstall 10.4 it freezes just after i select english as my installation language. I have been able to reinstall tiger using firewire but the ibook refuses to boot normally. I have also tried a different Hdd and Hdd Cable and no luck so far!!! I have been toying with it for months now and my patience is starting to grow short.

I could be very wrong but here goes...

when you boot up press on the iBook case just below the Apple and Ctrl keys .. and hold it down and see if the iBooks boot up in to OS X.. instead of just freezing ... use you hand or even put your elbow on it .. press pretty hard but not hard enough to crack the plastic .. remember the hard drive is right there close to where you are pressing.

If you just did an upgrade on the system to 10.4.11 it does take like 10 min to reboot the first time... so your

Background of why I am suggesting this .. is:

In open firmware and safemode if memory serves correctly will not use the Video proccessor to its fullest capeablilities ... but booting up in full use mode will this gets the GPU very hot ... and if there is either seperation on the BGA(ball grid array) for the GPU it will make it worse and will not boot...

and there is another chip on the bottom of the iBooks.. G4's that also have a tendancy to seperate from the logic board.. that will cause a similar problem.

Hope this helps.. if not its just a shot in the dark ... if this works.. you have a couple of options...

one is send it to a reflow shop .. 75$ total I think on ebay ...

or DIY (iffy at best) search BGA video processor G4 iBook on Google