Lot of pages and forums topics and menu items disappear

Hello everyone,

I'm a newbie in drupal and I recently install a community site for my neighborhood in Hebrew (http://ganey.co.cc).

Last week things gone bad, i don't know when or why:
1. The regular homepage disappear and i got the drupal's welcome page when i go to ganey.co.cc/node.
2. A lot of menu items don't show up in the Primary links but the still exist.
3. All the forums seem to be empty but the topics still exist.

I try to disabling caching, disabling Pathauto module and etc modules, but that dosen't work for me.

Now i set up a front page via the the frontpage view, but this and the other issue still itch me.

Any suggestions?
Thank for any help!

Ariel.