Which browser do you use on your PPC Mac? I use an old version of Firefox - wish I could use Chrome.
I tried TenFourFox for my old 17" iMac G4 and I found it slower than Safari or OmniWeb to be honest. Maybe I had the wrong version installed by I wasn't impressed by it. Now i'm exclusively using Safari 5 and it feels great, though it does lag sometimes. I might try SeaMonkey out and see how that works.