If you're looking to add a straightfoward drop down menu to an arbitrary image link on your page, you're probably better off with Anylink CSS menu. After following the instructions on that page, for Step 3, your HTML would look something like this:
Code:
<!--1st anchor link and menu -->
<a href="#" onClick="return clickreturnvalue()" onMouseOut="MM_swapImgRestore()" onMouseOver="MM_swapImage('Collections','','images/collectionsroll_06.gif',1); dropdownmenu(this, event, 'anylinkmenu1') "><img src="images/index_06.gif" name="Collections" width="99" height="20" border="0"></a>
<div id="anylinkmenu1" class="anylinkcss">
<a href="http://www.dynamicdrive.com/">Dynamic Drive</a>
<a href="http://www.cssdrive.com">CSS Drive</a>
<a href="http://www.javascriptkit.com">JavaScript Kit</a>
<a href="http://www.codingforums.com">Coding Forums</a>
<a href="http://www.javascriptkit.com/jsref/">JavaScript Reference</a>
</div>
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