Question

I am new to Javascript & relatively new to HTML. I would like to know what language(pure html or Javascript & html) I should use & some suggestions of an algorithm in order to do the following:

Place 4 squares on a background but position them diagonally. Each square is a link you can click to go to a different page. So how would I be able to position html elements diagonally like my picture below?

http://i54.tinypic.com/2v7uw5u.png

I believe my code would look like this:

<script>
    function positionIt()
    {
        var screenW = // javascript function to get screen width??;
        var screenH = // javascript function to get screen height??;

        var sq1 = document.getElementById( "square1" );
        var sq2 = document.getElementById( "square2" );
        var sq3 = document.getElementById( "square3" );
        var sq4 = document.getElementById( "square4" );

        // What javascript functions set a elements x,y positions?
        // Should I use another way of positioning the square (not by absolute terms)
        sq1.setXPos( screenW / 4 );
        sq1.setYPos( screenH / 4 );

        sq2.setXPos( screenW / 3 );
        sq2.setYPos( screenH / 3 );
    }
</script>

// OR if I use css
.menu { background-color: blue; }
/* Position the square in absolute terms diagonally */
#square1 { x=200; y=200; }
#square2 { x=300; y=300; }
#square3 { x=400; y=400; }
#square4 { x=500; y=500; }

<div class="menu" onload="positionIt()">
    <a id="square1" href="home.html"><img src="square.jpg" /></a>
    <a id="square2" href="home.html"><img src="square.jpg" /></a>
    <a id="square3" href="home.html"><img src="square.jpg" /></a>
    <a id="square4" href="home.html"><img src="square.jpg" /></a>
</div>

Answer 1

Live Demo
Live Demo (with left properties order changed to match your mockup)

I tried to keep to the numbers you asked for.

HTML:

<div class="menu">
    <a id="square1" href="home.html"><img src="http://dummyimage.com/100/f90/fff" /></a>
    <a id="square2" href="home.html"><img src="http://dummyimage.com/100/f90/fff" /></a>
    <a id="square3" href="home.html"><img src="http://dummyimage.com/100/f90/fff" /></a>
    <a id="square4" href="home.html"><img src="http://dummyimage.com/100/f90/fff" /></a>
</div>

CSS:

.menu {
    background: blue;
    width: 800px;
    height: 800px;
    position: relative
}
/* Position the square in absolute terms diagonally */
#square1 { position:absolute; left:200px; top:200px; }
#square2 { position:absolute; left:300px; top:300px; }
#square3 { position:absolute; left:400px; top:400px; }
#square4 { position:absolute; left:500px; top:500px; }

How does this work? See: http://css-tricks.com/absolute-positioning-inside-relative-positioning/