The answer to your question (title) is to replace
document.getElementById('about').href = '#';
with
$('#about').attr('href','#');
I have no idea if this will actually help you solve your problem, though, since I really don't know what you are trying to do. Based on your comments and code sample, it appears that you are trying to do some sort of wizard, but I have no idea how it would actually work given what you've posted.
Update:
Maybe something like:
<a href="link.php?test=true" onclick="request(this)" target="_blank" class='request'></a>
<a id="step2" href="next.php">Step 2</a>
<script language="javascript">
$(function() {
var requests = 16;
$('#step2').click( function() {
alert('Not finished');
return false;
});
$('.request').click( function() {
var $this = $(this); // save jQuery reference to element clicked
// swap indicator image source
$this.find('img:first').attr('src','images/clear.gif');
// if the number of flipped indicators equals the number of requests
// remove the click handler from the step 2 link
// this removes the alert and allows the user to proceed
if ($('.request img[src="images/clear.gif"]').length == requests) {
$('#step2').unbind('click');
}
...do something with the href for this request via ajax???
// replace this handler with one that simply returns false
// and remove the href since we're done with this request
$(this).unbind('click').attr('href','#').click( function() { return false; } );
// stop the default action for the request
return false;
});
</script>