If your browser is IE based you can use this activeX from meadroid:
http://www.meadroid.com/scriptx/index.asp
I have used it in the past and it permits to control the Printer attributes.
Here is an example from mmeadroid documentation:
<script>
function printWindow() {
factory.printing.SetMarginMeasure(2); // set inches
factory.printing.header = "This is MeadCo";
factory.printing.footer = "Printing by ScriptX";
factory.printing.portrait = false;
factory.printing.leftMargin = 1.0;
factory.printing.topMargin = 1.0;
factory.printing.rightMargin = 1.0;
factory.printing.bottomMargin = 1.0;
factory.printing.copies = 1;
factory.printing.printBackground = true;
factory.printing.Print(false);
factory.printing.WaitForSpoolingComplete();
// navigate or close browser here //
}
</script>