This is where your code is blocking:
<?php echo $this->getMenuLevel($this->getMenuArray()); ?>
Most probably $this->getMenuArray() is generating the error. Inside getMenuArray() there is _buildMenuArray() function which is responsible for creating menu nodes. My guess is that there is ACL permission admin access problem which is blocking creating the nodes. Try to manually delete all cache, session and locks data from /var/cache, /var/session and /var/locks to see if that solves the problem.