I am actually really curious how you get this to work with iWeb. I would be interested to know. I haven't ever tried it using iWeb, only dreamweaver, but I will try to help a bit.
You need to make sure that you can set up shadowbox in the head on your page. This is where I don't really know what to suggest. iWeb tends to hide all of these, however I suppose you could add it after you publish the site. Open the HTML in any text editor and add the set up there. Add this within the <head> tags somewhere
<link rel="stylesheet" type="text/css" href="shadowbox.css">
<script type="text/javascript" src="shadowbox.js"></script>
<script type="text/javascript">
Shadowbox.init();
</script>
make sure that shadow.css and shadowbox.js are actual paths to these files. (for example if you have a folder named "shadowB" in your root folder you will change these to "shadowB/shadowbox.css" and "shadowB/shadowbox.css" respectively. Otherwise just throw all of these files in the root folder and you will be good to go with the code above.
Second you need to add a reference in the link(s) that you want to open with shadowbox. So this is where you would add rel="shadowbox" into the links. Now a link is represented by <href> tags in HTML. So look for those. You can probably search for these with a text editor. A link goes like this in HTML: anything within parenthesis below are comments, not part of the html.
<href = "pictures/myPic.jpg"(the path to your media in quotes) title = "My Picture" (the name you would like to add for your media, gets displayed above shadowbox when it is used) alt="Click here to enlarge photo" (optional: adds accessibility text. When you hover over media this message appears or when the media fails to load. Not necessary but recommended) /> (closes your tag)
So it looks like this:
<href = "pictures/myPic.jpg" title = "My Picture" alt = "Click here to enlarge photo" />
All you do to add shadowbox (assuming it is setup in the head correctly) is add rel="shadowbox" between the media path and the media title. So in our example:
<href = "pictures/myPic.jpg" rel="shadowbox" title="My Picture" alt= "Click here to enlarge photo"/>
in the line that you posted, you can find this part near the end of that line that you added. If you follow that line from the back to the front you can see that we pass map, coords, alt, then title. Now you would add rel = "shadowbox" before title="soandso" but after the file path. So it would look like this.
<area href="test_files/90s_web.mov" rel="shadowbox" title="test_files/90s_web.mov" .... />
I hope this makes a bit more sense of your dilemma. Let me know if you get it to work.
