Q: My ibook g4 when starting up stays on the grey logo screen with the loading circle , but won't do anything further I left it on for two days straight to seeif it needed time to load but still nothing please what do I do I have a lot of important things on

Have you tried starting in SafeBoot mode?

See the first link below to read about attempting startup.

If that works after applying instructions to use it correctly,

one can look into system logs in Console to see if any

records or old reports leading up to the time of trouble

appear, as sometimes these exist & offer evidence.

You can use Disk Utility in the Utilities folder to Verify

the hard disk drive; also repair disk permissions, there.

A failed startup such as you state could be due to bad

software in the boot section of the drive, or a hard drive

that could be bad. Some other possibilities exist.

Troubleshooting your issue to attempt resolution...

•Mac OS X: Gray screen appears during startup

http://support.apple.com/kb/ts2570

•Spinning beachball (cursor wheel) in all apps, hung startup - the X Lab:

http://www.thexlab.com/faqs/sbbod.html#Anchor-SBBOD_continuous_all_apps_hung

•How to fix common mac startup problems - cult of mac:

http://www.cultofmac.com/50685/how-to-fix-common-mac-startup-problems-macrx/

If you have the install-restore DVD or install disc of the

most recent OS X the computer is running, you could

see if the computer may boot from it (hold C key down

immediately after start chime, keep holding it until you

see the desktop or a login, if the latter, enter password

and let it continue; if you get to the Installer window,

then you can choose from the menu bar choices to find

and use Disk Utility in the installer DVD, to see if you

can repair the hard disk drive. It may repair, or it may

say the hard drive can't be repaired. This helps to tell

what is wrong; esp. if it failed. A replacement ATA-IDE

hard disk drive of 2.5" size, about 4500 to 5400 RPM

of correct spec for the computer could be installed.

If you do not have the correct system DVD or one newer

than the original software the computer shipped with,

depending on the iBook G4 specs, you could use either

retail Tiger 10.4 DVD or a Leopard 10.5 DVD. An iBook G4

with 800MHz processor can't use Leopard OS X. Also

DVDs from other computers (grey label) usually won't

work unless they are identical series build replacement.

Discs from intel-based mac or other computers won't do.

Good luck!

Data Recovery using a Firewire external hard disk and the correct aforementioned operating systems is probably a good idea if there is no backup:

https://discussions.apple.com/docs/DOC-1689

Firewire 400 (6 pin) to Firewire 800 cables can be used in this process with http://www.macsales.com/ hard drives.