in that the boot sequence was not completed.
The usual fix is to shut it down and reboot.
However, if this happens everytime you start up the computer, then the next step is to reinstall the OS using the OS X install disks, but I will bet that your benefactor failed to pass along either the original disks that came with the computer or the installation disks for the OS that is installed on that machine.
Without those disks you are very limited as to what you can do to fix this problem.
Try restarting the ibook and as soon as you hear the chimes, hold down the shift key. Keep it down until you see the spinning gear under the Apple.
If it starts correctly, you have something correct in the additional things that the OS loads.
Let us know how you get on, and whether you have any System disks for this machine, and we can go from there.
I have an ibook g4 that was given to me...after logging in it comes up with a blue screen with designs I believe standard for the wallpaper. But there are no icons or anytype of menu. Ive moved the mouse around and clicked to see if it was hidden but to no avail nothing happened, also i put a cd in and it didn't play... i am new to the mac arena and need all the help i can get...