I have your problem dude, I bought 10.2.3 or something first, then upgraded to .8 via net when it came out. So i've been dealing with all the retarted "no mountable file systems" messages, the horrible wait times, and well most regreatably the noncompliance with basically anything that is Good for Apple ie. Parallels, All apps newer than '06, Skype, Skype, and Chelsea Clinton.
Oh, and the most suething thing is I have a (nonexistent)PowerBook G4, So I can not install any of the 10.3's or 10.4's that I have come my way.