Personalmente farei così:
Codice PHP:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Nome Tab.</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css">
body
{
text-align: center;
}
#container
{
width: 800px;
margin-right: auto;
margin-left: auto;
}
#box1
{
background: #FF0000 url(cartella/box1.gif) no-repeat;
width: 260px;
height: 240px;
}
#box2
{
background: #00FF00 url(cartella/box2.gif) no-repeat;
width: 370px;
height: 240px;
}
#box3
{
background: #0000FF url(cartella/box3.gif) no-repeat;
width: 170px;
height: 80px;
}
#box4
{
background: #FFFF00 url(cartella/box4.gif) no-repeat;
width: 170px;
height: 80px;
}
#box5
{
background: #FF6600 url(cartella/box5.gif) no-repeat;
width: 170px;
height: 80px;
}
#box6
{
background: #FF00FF url(cartella/box6.gif) no-repeat;
width: 260px;
height: 40px;
}
#box7
{
background: #00FFFF url(cartella/box7.gif) no-repeat;
width: 370px;
height: 40px;
}
#box8
{
background: #999999 url(cartella/box8.gif) no-repeat;
width: 170px;
height: 40px;
}
.box
{
float: left;
}
</style>
</head>
<body>
<div id="container">
<div id="box1" class="box"></div>
<div id="box2" class="box"></div>
<div id="box3" class="box"></div>
<div id="box4" class="box"></div>
<div id="box5" class="box"></div>
<div id="box6" class="box"></div>
<div id="box7" class="box"></div>
<div id="box8" class="box"></div>
<div style="clear: both"></div>
</div>
</body>
</html>