When trying to delete an app, it says it cannot because it is not mine.

Hello,

The best way to upgrade from Mac OS X 10.2 is to obtian a retail copy of Mac OS X 10.4 or if the PowerBook G4 is above 876mhz with 512MB or higher memory, then obtain a retail copy of Mac OS X 10.5

To delete old programs you need to be either be, the system administrator (Her account ) or the root user.

To enable the Root user, you need to do the following: http://support.apple.com/kb/ht1528

Once logged in as Root you can then delete the old applications.

Best of luck

I believe the 10.4 and 10.5 are not available for purchase anymore from Apple, am I right?

Correct. You will have to look on eBay or Amazon for those old versions of OS X. Make sure you get the black retail install disks and not somebody's grey update disks.

No idea what they are asking for Tiger, but Leopard currently sells for around $200. If you can run Leopard:

http://support.apple.com/kb/SP517

go for that, as it includes more up to date versions of Safari than Tiger, the latter now struggling to keep up with the current internet.

Tiger is no longer available at the Apple Store. For other sources, do a Google search for MA453Z/A (10.4.6), MA190Z/A (10.4.3) and M9639Z/A (10.4). Also look on eBay. Be sure & buy a retail version (black with silver X)

and not a model specific version (gray) (See http://discussions.apple.com/thread.jspa?threadID=1976068 Can I use another Mac's system restore disc on my Mac?.

After you install the base 10.4.x, update to the final Tiger version 10.4.11. Here's the link for the 10.4.11 combo update http://support.apple.com/kb/TA24901?viewlocale=en_US

Look at this link Mac OS X v10.4 Tiger Installing Software Support Page

http://www.apple.com/support/tiger/install/

You can also download the Tiger Installation and Setup Guide

http://manuals.info.apple.com/en/Tiger_Install_Setup_Guide.pdf

When you upgrade the OS, do it via Archive & Install. See About the Archive and Install feature http://support.apple.com/kb/HT1710

Be sure to select Preserve Users & Settings. Also, repair permissions before and after the install.

Mac OS X 10.5 Leopard installation system requirements

http://support.apple.com/kb/TA24950

Look on eBay or Google the installer part numbers to possibly find at an on-line store. Here's what to look for:

MB427Z/A Leopard 10.5.1 install DVD

MB576Z/A Leopard 10.5.4 install DVD

MB021Z/A Leopard 10.5.6 install DVD (single user)

MB022Z/A Leopard 10.5.6 install DVD (5-user family pack)

Installing Mac OS X 10.5 Leopard

http://support.apple.com/kb/HT1544

Mac OS X 10.5 Leopard Installation and Setup Guide

http://manuals.info.apple.com/en/leopard_install-setup.pdf

After you install the base 10.5, download & install the 10.5.8 combo update at http://support.apple.com/downloads/Mac_OS_X_10_5_8_Combo_Update

The DVD should look like this

Caution - Leopard does not support classic mode. So, if you currently open OS 9 apps in classic mode, you won't be able to do this if you upgrade to Leopard.

 Cheers, Tom 😉