Site has vanished after 3.2 Upgrade

Help! After upgrading my WordPress to 3.2, my site is gone! It directs to this error message:

Fatal error: Call to undefined method Arras_Widget_Tag_Cloud::WP_Widget_Tag_Cloud() in /home7/lasercol/public_html/wp-content/themes/arras/library/widgets.php on line 404

Have I destroyed everything? Is there an easy fix for this? Here is my site URL:

http://www.lasercola.com

Any Help would be greatly appreciated.