Revert OSX

I have an iBook g4 1.07 Ghz PPC with 512 RAM and I recently put 10.5.6 OSX onto it.

I'm just wanting to know if it's optimal to be running this version of OSX rather than my old 10.4, as I'm having some issues with my Airport and some performance lag and the iBook used to run a lot smoother and there were no internet issues.

I don't mind switching back at all especially if it means better wi-fi/internet.

I have a similarly configured iBook with a bit more RAM and it is slower on 10.5 than on 10.4. I suspect that this is simply the fact that the machine is 5 years old at this point.