I see this error when I try to open the image:
Warning: file_exists() [function.file-exists]: open_basedir restriction in effect. File(/usr/local/apache/htdocs/wp-content/uploads/2011/03/6126_marquee_512x288.jpg) is not within the allowed path(s): (/home/:/usr/lib/php:/tmp) in /home/a5087719/public_html/wp-content/themes/LondonLive/thumb.php on line 792
The "open_basedir" restriction is a setting at the server configuration end so would need fix it. You can send them a copy of the error along with a link to your site.
Actually on looking at it more closely it seems like are somehow calling a file outside your own site's directory on the server:
I don't see the name of your home directory - i.e. /home/a5087719/ - in that path.
I'm not sure if that's a problem at your host's end or in your WP configuration.
In your WP admin area, in Settings > Media - what do you have in the media uploads field?