Hello,
It's actually an issue with the browser itself, not the template. The newest version of Opera is not properly rendering certain javascripts, specifically mootools, which is used throughout Joomla. You can read more about it from here:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=28804Unfortunately, there is nothing that can be done until Opera releases an update for their browser.