1/. If you're targeting a printer, make 'factory.printing.printer' your first line so that every subsequent attribute is called against that specific printer.
2/. Unprintable areas:
Open a 'vanilla' pane in IE and go to File | Page Setup.
Set each margin measure at "0" and OK out of the dialog.
Now go to File | Page Setup.again.
The margin values shown now are the unprintable area values that the printer driver returns to Windows, and less than which you can't set.
Cheers
Jerry