To do this you are going to need to edit some html. If you don't know how to do this then have a look at How to edit your html.

Insert the image into your page then click "edit html". Find a part that looks like this:

<a style="border: 0pt none ; background-color: transparent; margin-left: 1em; margin-right: 1em;" href="trans.png/trans-full;init:.png" imageanchor="1"><img src="/trans.png/trans-medium;init:.jpg" style="border: 0pt none ;"></a>

Now change the bold section to the url of what ever page you want the image to link to