major problems upgrading software

[Jenny Editor]

Please can anyone help?

I have an ibook G4 running a OSX 10.3.4
I was upgrading software that was available to me free - I have never done this before but it seemed easy - I just typed in my password and it started.
There were 18 upgrades - the biggest being os X10.3.9
I left it running and checked up periodically and all was well but then I came back and the screen was blank.
I have tried restarting by taking out the battery and it starts off ok but when it gets to 'Login Window starting' where it sits for several minutes with the blue bar shimmering and then the screen just goes blank.
I have tried a 'Safe boot' but the same thing happened.
I am very desparate as I need the laptop today and the Applecare line is helpfully closed on a Sunday!!

Jenny Editor

[SatCure]

Will it boot up OK from the original Installation disc?
Have you a copy of DiskWarrior or similar utility?
Have you another Mac available?
Did you make a complete backup of all important files before updating?
Did you "Repair Permissions" before updating?
Was there plenty of room on the Hard Drive for the updates?

(For anyone else contemplating an update, make a note of these questions! If any answer is "no" don't begin the updating process).