I am relatively new to Javascript(& new to CodingForums.com) and I am trying to achieve a look that I can't achieve with just HTML.

I am working on my personal photography site and I would like to mouseover a thumbnail image in one iframe and have it load into a different iframe.

Currently the setup is as such: Table including, Row 1 not important, Row 2 has two iframes of different sizes(for thumbs then main image+text), and Row 3 is the Navigation bar at the bottom. When clicking on a gallery title in the Nav Bar, I have the image thumbnails loading to the first iframe on the left. I want to mouse over them and have the larger image load in the 2nd iframe to the right. How do I achieve this? I know how to do regular HTML links as such with targeting to the the 2nd iframe, but I have had no luck producing a functioning script. What do I need to achieve this? Any help is greatly appreciated!

-Dennis