Why would want to clear the Printer and Spool files? If you lose the ability to print in OS X 10.1 and the Classic environments, booting to 9.X.X and printing is not a real solution. But clearing the Printer and Spool files may be a quick way to restore your printing capabilties. To clear the queue and printers:
- Open "Print Center" in Applications -> Utilities
- Click on the "PrintCenter" menu, then press and hold the option key and select "Quit Print Center". This will bring up a dialog box asking you if you're sure you want to delete your printer and any jobs waiting to be printed. Select "Yes".
- Open Print Center again and re-add your printer. I've had this work with Apple, Epson, HP and Lexmark printers.