restart the machine holding down the option[alt] key you'll be presented with either one or two options to boot into jaguah[osX] or classic[os9]...only one option, then there is no classic startup system file, there might be a network option, if you have no mac network, then it's not do-able.

you should skip classic and move on to poser 5, unless there is serious issue with osX and poser5[which is why i'm here, searching] i bet either upgrade will be about equal cost. if one of your install disks has a big 9 on it, then that will be your classic install disk, if not you are SOL. i have an ibook, contact me offlist if you like[former bournemouth resident ; ^]