I have successfully installed Debian Lenny w/LXDE desktop and Openbox wm on several iMac G3s and it works well. With a special workaround I also have Iceweasel 3.5 and it works fine (Rebranded Firefox.) I had to choose gnash over SWFDEC for flash as SWFDEC puts a big play button on each flash object ...

Because I have never bothered to download Puppy 4.2, I only learned about this problem with Broadcom wifi devices recently:
In 4.2 Final..bcm43xx is still being a problem...for those of you who wants a workaround..just edit /etc/rc.d/MODULESCONFIG

That's because the new Broadcom b43/b43legacy ...