First (and off-topic), I'd recommend going to
www.facebook.com/username and setting up a better Page URL for your Facebook Page. It's better than the long page name you have now, which can help promote your Facebook Page a little better.
As to your specific issue about the image being used, on that page, there is no Open Graph image tag set to tell Facebook what to use. I'm not sure what you're using to display the images on that page, but if it's a Joomla content, please enable the Open Graph - Content plugin. If there are other extensions you have installed that we installed Open Graph plugins for, it's best to enable those plugins as well. Those plugins will try to detect and automatically select a good image for each page in those extensions.
If we don't have an Open Graph plugin for your extension, you can add the following 'tag' to the output of any page to specify the image that Facebook should use:
{SCOpenGraph image=http://domain.com/link-to-your-image.jpg}
To test, you can run any page through the
Facebook URL Debug Tool
to see what Facebook 'sees' about your page.
I hope that gets you started, but if you have any questions, just let me know.
Thanks,
Alex