I am sure that this must be really simple but I'm not a java programmer and have absolutely no idea where to start. Please help.

I am using this code:

<script type="text/javascript">
var pwin;
function printImg() {
pwin = window.open(document.getElementById("imgMain").src,"_blank");

I want to adapt it so that I can resize an image on print in one option and print multiple images in another option. I have no idea how to do this. Can anyone help? Many thanks.