Alright, so I have a Power Mac G5 and an HP PC. They are both connected to the internet via Airport Extreme. The G5 has automatically picked up the "shared documents" and has me connected to it as "SharedDocs" server drive. However, the PC (with MacDrive) isn't getting any "shared" folders from the Mac. Is this doable? (By the way, the representation of the PC with the BSOD icon is bitterly accurate: the computer did crash badly the other day, requiring system recovery.)

it is not as simple, there are many places, where the error can reside.
( osx leopard on pc does´nt like self assigned ip adresses in the LAN,
some kexts for the ethernet chip don´t support bonjour properly or with delay,
file sharing must be enabled in sys prefs ( the idiot error, but happened to me too)