Sorry, I just got back to my computer. Your page is loading now (probably it was a maintenance thing). Did you change the theme? It seems to be working.
The menu bit I recommended you is a new feature in WP 3.0, it could help if the dev of your theme updated the menu and forgot to make it fall back to the traditional way of doing menus. I am not familiar with the theme you are using, so I cannot give you further advice, I am afraid.
Just in case you didn’t do it yet: Did you test it in different browsers?
Best of lucks.