you would need to use an if statement to either the link address with or without the a tag:
assuming you use a recordset to return the link address and link label, and use a column named active, the code would look something like this:
<?php if($row_recordsetName['active'] == 1) { ?>
<a href="<php echo $row_recordsetName['link'] ?>">
<?php } ?>
<php echo $row_recordsetName['linklabel'] ?>
<?php if($row_recordsetName['active'] == 1) { ?>
</a>
<?php } ?>