I'm not aware of any built-in way to do this.

In case it inspires any thoughts, what are the normal parameters vs. page-specific parameters, primarily margins?

That might be possible via a GreaseMonkey user script, by setting the @include address to a specific domain.

http://wiki.greasespot.net/User_script

This is an example of a script I found a few years ago to bypass a fault in Firefox when printing the Courier font.

// ==UserScript==
// @name           Fix Courier Bug 
// @namespace      http://userscripts.org 
// @description    Replaces "Courier" with "Courier New" font 
// @author         Dan 
// @include        *
// ==/UserScript==
var elementList = document.getElementsByTagName('*');
for (var i = elementList.length - 1; i >= 0; i--) {
    var elementItem = elementList[i];
    var ff = getComputedStyle(elementItem, '').fontFamily;
    var oldff=ff;
    ff = ff.replace('Courier New', '1234567890qwertyFONT');
    ff = ff.replace('Courier', 'Courier New');
    ff = ff.replace('1234567890qwertyFONT','Courier New');
    elementItem.style.fontFamily = ff; 

Sorry, I can't help you with writing a script.

The standard parameters are 100% and all margins at .5 inches.

Is there a way to open 2 different Mozilla browsers at the same time, each opening different web sites with different page parameters?

Also, do you know how I can make Mozilla open automatically when my computer boots?

Hi MartyCohen, what would the parameters be for the site that needs different parameters?

One way to start a program automatically is to place a shortcut in the Startup folder. I found a Windows Vista/Windows 7 help article on this, but I think the procedure in XP is almost identical.

http://windows.microsoft.com/en-us/windows/run-program-automatically-windows-starts