Sades,
The best way to do would be to use a a hyperlink and target the actual frame.
Let's say you have two frames on your page - one that is Small and one that is Big. Make sure you add the name attribute to your frames - for this example - name the small one "Small" and the big one "Big".
Then just make your hyperlink as such:
<a href="samepage.htm" target="Big">Hyperlink text or image here</a>
Just make sure if you are staying on the same page that you define the same page in the href attribute or use "#" instead.
Regards,
Brian
