Código HTML:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Bienvenido</title>
<script language="JavaScript">
function muestra(id){
if (document.getElementById){
var el = document.getElementById(id);
el.style.display = (el.style.display == 'none') ? 'block' : 'none';
}
}
window.onload = function(){
muestra_oculta('contenido_a_mostrar');
}
function oculta(id){
if (document.getElementById){
var el = document.getElementById(id);
el.style.display = (el.style.display == 'none') ? 'block' : 'none';
}
}
</script>
<style type="text/css">
.Estilo1 {font-family: Arial, Helvetica, sans-serif}
.Estilo2 {font-size: 14px}
</style>
</head>
<body onload="MM_preloadImages('Autos2.png')" bgcolor="#FFFFFF">
<div align="center">
<p align="center" class="Estilo1"><img src="http://i.imgur.com/4uRRJ.png" width="206" height="120" alt="" longdesc="Grupo Asistencia" /></p>
</div>
<!--menu -->
<a style='cursor: pointer;' onMouseOver="muestra('texto1')" onmouseout="oculta('texto1')"><img src="http://i.imgur.com/lBSa2.png"></a>
<a style='cursor: pointer;' onMouseOver="muestra('texto2')" onmouseout="oculta('texto2')"><img src="http://i.imgur.com/BVH0E.png"></a>
<!--fin menu -->
<!--div ocultos -->
<div id="texto1" style="display:none">
<img src="http://i.imgur.com/N8GvO.png">
</div>
<div id="texto2" style="display:none">
<img src="http://i.imgur.com/4uRRJ.png">
</div>
<!--fin div ocultos -->
</body>
</html>