The below line opens a selected index from a drop down in a browser window. The form field is in a div called "contents". I need to know the syntax needed to open this selection in another div on the same page called "main". The "_top" location opens the file in a new window. I want to open this on the same page. Do I need javascript for this?
Code:
onchange="window.open(this.options[this.selectedIndex].value,'_top')" style="text-align: center">
Here is all the code for my file:

Code:
<!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 content="text/html; charset=utf-8" http-equiv="Content-Type" />
<title>Untitled 1</title>
<style type="text/css">
.banner {
	background-color: #000000;
	width: 100%;
	height: 25px;
}
.contents {
	width: 180px;
	height: 560px;
	background-color: #0000FF;
}
.main {
	width: 100%;
	height: 100%;
	background-color: #006600;
}
</style>
</head>

<body>
<div id="banner" class="banner">
</div>
<div id="contents" class="contents">
<form action="../">
&nbsp;&nbsp; <br />
&nbsp;
<select onchange="window.open(this.options[this.selectedIndex].value,'_blank')" style="text-align: center">
    <option value="">Choose a destination...</option>
    <option value="http://www.directpaintsaleswa.com/brianschmit/WXRECORDS/images/yearly/Portland1981-2010.png">CLIMATE</option>
    <option value="http://www.directpaintsaleswa.com/brianschmit/WXRECORDS/images/yearly/2011.png">2011</option>
    <option value="http://www.altavista.com/">ALTAVISTA</option>
    <option value="http://www.amazon.com/">AMAZON</option>
    <option value="http://artlung.com/">ARTLUNG</option>
</select>
</form>
</div>
<div id="main" class="main" style="position: absolute; width: 1148px; height: 564px; z-index: 1; top: 43px; left: 192px">
</div>

</body>

</html>