You can try the following as obviously you have a botched update:
How to Perform an Archive and Install
An Archive and Install will NOT erase your hard drive, but you must have sufficient free space for a second OS X installation which could be from 3-9 GBs depending upon the version of OS X and selected installation options. The free space requirement is over and above normal free space requirements which should be at least 6-10 GBs. Read all the linked references carefully before proceeding.
1. Be sure to use Disk Utility first to repair the disk before performing the Archive and Install.
Repairing the Hard Drive and Permissions
Boot from your OS X Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Installer menu (Utilities menu for Tiger.) After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list. In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive. If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported, then quit DU and return to the installer.
If DU reports errors it cannot fix, then you will need Disk Warrior (4.0 for Tiger) and/or TechTool Pro (4.5.2 for Tiger) to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
2. Do not proceed with an Archive and Install if DU reports errors it cannot fix. In that case use Disk Warrior and/or TechTool Pro to repair the hard drive. If neither can repair the drive, then you will have to erase the drive and reinstall from scratch.
3. Boot from your OS X Installer disc. After the installer loads select your language and click on the Continue button. When you reach the screen to select a destination drive click once on the destination drive then click on the Option button. Select the Archive and Install option. You have an option to preserve users and network preferences. Only select this option if you are sure you have no corrupted files in your user accounts. Otherwise leave this option unchecked. Click on the OK button and continue with the OS X Installation.
4. Upon completion of the Archive and Install you will have a Previous System Folder in the root directory. You should retain the PSF until you are sure you do not need to manually transfer any items from the PSF to your newly installed system.
5. After moving any items you want to keep from the PSF you should delete it. You can back it up if you prefer, but you must delete it from the hard drive.
6. You can now download a Combo Updater directly from Apple's download site to update your new system to the desired version as well as install any security or other updates. You can also do this using Software Update.
Tip: Always run Disk Utility and Repair Disk Permissions BEFORE and AFTER updating or upgarding software, especially system software. Disk Utility is in your Applications/Utilities folder.
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Also, select your MacintoshHD icon on your Desktop, then click Command + I on your keyboard. That will trigger the Get Info window. Click the General tab down. Look and see how much available drive space you have. Never allow the free drive space to fall below 15% of the total drive. That can cause a myriad of problems if you don't have enough free drive space.
The problem is that the botched update has corrupted your system, so it must be reinstalled. You can take my procedure that will not erase your drive, or you can just do an Erase and Install with the Installer Disc which is a simple reinstallation but will erase everything on your hard drive. Basically the choice is yours.
Alright thanks. If it becomes unbearable or if I can't find another option, I'll try your method.
But the thing is it would have minor problems like this before I installed the update, like sometimes something would randomly freeze and shut down or AIM wouldn't work and I would have to switch to iChat. I just chalked it up to just slowing down because of excessive use.
Then when I installed the update everything became much worse.
You are ok on available disk space but if you decide to do an Archive and Install, you should free up even more space.
If it were me, I'd back up everything vital... music/images/video, important data and do a complete Erase and Install.
It's very easy, takes little time. You need your restore disk(s), I think there are five. When you have backed up all your files... do this:
Shut down the iBook. Now, hold down the C key while pressing the power button and inserting disk number 1 all at the same time. An Installer window will open. Click English. Now, just follow the onscreen instructions. It's just that simple. I strongly advise you not do an Archive and Install with just 19GB free space... do the Erase and Install... the instructions will be right on the Installer window. If you need more help, just post back. You can do this.
It will go back to all the default settings and system software. You won't have any 3rd party software that you might have downloaded and installed. No, you don't have to reinstall each program separately.
Just use your restore disk(s).
** Don't forget... run Disk Utility and Repair Disk Permissions BEFORE and AFTER ***
As it clearly states in the Disk Utility/First Aid window, you cannot repair your hard disk from the same start-up disk. Reboot from your install disk (holding down the C key). Once it opens, select your language, and then go to Disk Utility from the Utilities menu. Select your hard disk as before and click Repair.
Once that is complete reboot again from your usual start-up disk.
Or to put it into even simpler language:
The hard disk inside your Mac is your start-up disk, the one you start your Mac from. It cannot repair itself, so you need instead to start up from the install disk that came with your Mac - this why it is so important to have it.
Place that DVD in your superdrive and go to the Apple menu and click on Restart. Hold down the c key on your keyboard until your Mac has started up. This will take a bit longer than when you start from your hard disk.
You are NOT going to install anything, but just select English as your language (assuming that it is!), and ignore the next (install) window that appears. Go to Utilities in the menu at the top of the screen, and go to Disk Utility. Select your Hard Disk and click on repair.
This will take a little while and you will see all kinds of messages in the window, all of which you can ignore. Finally it will say Disk Repaired, and you then restart again without holding down the c key, in order to start up again from your built-in hard disk.