If you look at the following page:
http://tinyurl.com/5s9q6ov

And then click the video thumbnail on the right (see attached image):

I am having trouble opening up a Vimeo video using Fancybox.

I have taken the iframe embed code off my Vimeo account, however I am getting js errors popping up in Internet Explorer. I get about 3 of them which I can cancel and then I am able to watch the video.

Does anyone know why this might be? Could it be that I am not executing Fancybox for an iframe properly?

Here is the HTML where the thumbnail is:

<div class="grid_3 alpha thumb">
                    <span class="icon-play"></span>
                    <input type="hidden" value="137" class="thumb-media-feed">
                                            <a href="#media-137" class="fancybox-inline"></a>
                                        <img alt="Behind the Golden Gates" src="http://www.mattpealing-server.co.uk/~handstan/wp-content/uploads/2011/06/Screen-shot-2011-06-20-at-11.57.20-160x86.png">
                </div>

And here is how I am executing Fancybox:

$(document).ready(function() {
    $('.fancybox-inline').click(function() {
        return false;
    });
    $('.fancybox-inline').fancybox({
        'transitionIn'    : 'elastic',
        'transitionOut'    : 'elastic',
        'titlePosition'    : 'over',
        'hideOnContentClick' : false,
        'autoDimensions' : false,
        'width' : 580,
        'height' : 410
    });
})

Not only that, but I am getting another issue in Firefox. If you open the video by clicking the thumbnail then the video opens fine, however if you close it and then re-open it then I just get a blank white box opening up with no video inside it!

Could this again be caused by me not having set up Fancybox properly?

Works for me Ok.

Wow, I only recently got an email informing me of your reply!

I managed to fix it by looking at the code on this page:
http://fancybox.net/vimeo

Doesn't even look like a proper public page for the website though, as if it's just a little test that the plugin author did.