Can I use this guide to install apps into my ubuntu install? I just want to make sure I dont get some x86 stuff and mess up anything.

guide is HERE: http://ubuntuguide.org/

That guide is for the old version of Ubuntu (Hoary), and there are now better places to get information from on the forum. You will always have to be careful and make sure you are getting the right packages though... other than that the guide and the Ubuntu forum is still very useful for configuration info. Check out the PPC-specifc forum for Breezy here:
http://ubuntuforums.org/forumdisplay.php?f=95

That was my post above. Also, the ubuntuguide.org link has not been updated in a while, but the new place to go for this information is ubuntuguide.squarecows.com. This new place is actually updated for Breezy (instead of Hoary), but at this time they only have information regarding x86. I'm sure that most of the information would still be helpful for PPC though.

EDIT: Looks like there is still a mirror of the older PPC guide for Hoary located here:
http://userlinux.net/pub/stuff/ubuntu/

The creator of this project was unable to maintain things after real-life issues, but I believe there is talk in the Ubuntu community of someone taking over for him. The above link helps out greatly though, and I'm sure it can be easily updated for Ubuntu 5.10.

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Joshua Purcell

Try to have a look at the Pegasos book : http://wikipeg.free.fr/ThePegasosBook

There is a tutorial to install Ubuntu 5.10.
There is also a tutorial to install MacOSX from your Ubuntu distrib.

you shouldn't be able to install any X86 stuff by using apt-get or synaptic. The apps are located in separate repositories.