Opening Links in the Same Window

[Colormeorange]

Hi, I know nothing about flash - only CSS/HTML. ._. Anyway, I'm working on a student website and I have the following code:

<script type="text/javascript">
<!--
var timeout = 500;
var closetimer = 0;
var ddmenuitem = 0;

// open hidden layer
function mopen(id)
{
// cancel close timer
mcancelclosetime();

// close old layer
if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';

// get new layer and show it
ddmenuitem = document.getElementById(id);
ddmenuitem.style.visibility = 'visible';

}
// close showed layer
function mclose()
{
if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';
}

// go close timer
function mclosetime()
{
closetimer = window.setTimeout(mclose, timeout);
}

// cancel close timer
function mcancelclosetime()
{
if(closetimer)
{
window.clearTimeout(closetimer);
closetimer = null;
}
}

// close layer when click-out
document.onclick = mclose;
// -->
</script>

And then at my menu bar...

<div id="menu">
<ul id="sddm">
<li><a href="homepage.com/about.html" onmouseover="mopen('m2')" onmouseout="mclosetime()">About</a>
<div id="m2" onmouseover="mcancelclosetime()" onmouseout="mclosetime()">
<a href="homepage.com/blahblahblah">Blahblahblah</a>
<a href="homepage.com/blahbarbar">Blahbarbar</a>
</div>
</li>

How would I make ABOUT open in the same window?
I think I know how to do the other two, but I'm not sure
Many thanks!