Currently Being ModeratedDec 13, 2013 7:06 PM (in response to Sandrelope)
There are no free Apple updates available for that configuration; the next step is to buy a Mac OS X 10.5 DVD from a source such as Amazon or eBay. Mac OS X 10.5 doesn't support Mac OS 9 applications.
Currently Being ModeratedDec 16, 2013 4:08 PM (in response to Sandrelope)
Some Powerbook G4s support dual 10.5/Mac OS 9 booting. For everything else, you either need an external firewire clone of your Mac OS X 10.4 system with Mac OS 9 included, or add a second hard drive internally in place of the optical drive with 10.4 to be able to upgrade to 10.5 and keep using Classic. That way you dual boot 10.5 & 10.4 w/Classic.