Your preferences for cover page will be saved as the new defaults if you click "Okay". Other default settings will not be affected.
A new check box entitled "Disk File" is made visible for Laserwriters. Clicking this will send the postscript output of a print job to a disk file instead of a Laserwriter printer. The file that is created will be titled "Postscript0". If a file of that name already exists, the new file will be called "Postscript1", and so on. This file may be located in one of 3 folders, depending on the application: it is probably made in the folder where the application lives. It may be in the folder where the document you are printing lives, or it may be made in your system folder.
This "Disk File" check cannot be made a default choice, so you must re-select it at each print job.