Hi John,
Your customer needs to change their default settings on their printer. To do this, go to Control Panel >> Printers and Faxes >> Right-click on the printer and go to Properties. Click Printer Preferences and change the orientation to landscape. Click Apply and then OK. Now when they go to print the report, it should be defaulted to be a landscape.
As for the XML question, you are correct. You will need
to
modify the report header using a callback and then add the appropriate
style information in the XSL file to render the barcode.