Can't get rid of "auto" printers

I sure hope I didn't overlook a solution to this - I recently installed a home network (Win/XP) and set each pc to use file/printer sharing. I really didn't need the printer part, but that was ok, at least until I discovered that one of the pc's repeatedly sets it's default printer to MY printer, so that I get that user's printouts. The same thing happens on my pc, my default printer keeps getting reset to the autoprinter in another part of the house.

I've tried to "delete" the printers using the "printers" dialog of Control Panel - the printer goes away for a moment, but returns later.

I've also un-checked the "scan for new network printers and folders" option under folder options, but nothing seems to keep the printers from appearing in my printers dialog (my printers appear in the OTHER user's "printers" window as well).

TIA!
steve