9 is old...
If there is not a particular reason for you using openSUSE 10.0, you could switch to the new 11.2 which will be out in the beginning of November.
If you want to stay with KDE 3.5, it is still available on 11.1, but not on 11.2. If you want 10, I would recommend 10.3, the revision that solved the problems incurred when Novell bought SUSE.
In general. a distribution like openSUSE is better upgraded with a new installation rather then an update. There are both live-cds and installation DVDs, with the DVD giving you more controll, and the installation process in itself is quick. Updating from 9 to 11.x might not go well, even updating to 10.3 might be a problem.
The quickness and ease of installation is relative to your hardware and any difficulties it presents, but that would be the same with any any distribution you installed.
Here is 10.3. If you go up the tree in the parent directory, you will find listings of other openSUSE distributions.
http://download.opensuse.org/distribution/10.3/iso/dvd/
If it is a question of ppc, there is a 10.3 DVD for the older Macs.