This is with reference to this thread How to make a pdf printout occupy the entire A4 page.
I am able to bring all the content into a single page, but even if I set the printer preferences to landscape format, it doesn't print it.
What could be the problem?
Are you setting the orientation attribute of the tag? That attribute controls the orientation of the page, and you should set it to landscape.
From the Seam documentation
orientation — The orientation of the page. Valid values are portrait and landscape. In landscape mode, the height and width page size values are reversed.