SQL Error Out Of Nowhere!?

[Jaske]

I don't know what happened but all of a sudden I began getting e-mails from my database for my forum and when I log into my admincp and try to go to options I get the following:

Database error in vBulletin 4.0.8:

Invalid SQL:

        SELECT setting.*, settinggroup.grouptitle
        FROM settinggroup AS settinggroup
        LEFT JOIN setting AS setting USING(grouptitle)
        WHERE settinggroup.displayorder <> 0
        ORDER BY settinggroup.displayorder, setting.displayorder;

MySQL Error   : Can't create/write to file '/tmp/#sql_5ed9_0.MYI' (Errcode: 22)
Error Number  : 1
Request Date  : Friday, January 21st 2011 @ 10:07:29 PM
Error Date    : Friday, January 21st 2011 @ 10:07:30 PM
Script        : http://www.**********.com/forum/admincp/options.php?null=0
Referrer      : http://www.**********.com/forum/admincp/index.php?do=nav

I set the forum up, let it go live 2 days ago with every recommended security addon to avoid being hacked so I'm pretty sure I haven't been hacked.

the forum itself works fine except the media library throws up this error:

LEFT JOIN media AS media ON (media.categoryID = media_category.categoryID)
        WHERE catOrder != '0'
        GROUP BY media_category.categoryID
        ORDER BY media_category.catOrder;

MySQL Error   : Can't create/write to file '/tmp/#sql_5ed9_0.MYI' (Errcode: 22)
Error Number  : 1
Request Date  : Friday, January 21st 2011 @ 10:07:07 PM
Error Date    : Friday, January 21st 2011 @ 10:07:08 PM
Script        : http://www.**********.com/forum/media.php
Referrer      : http://www.**********.com/forum/forum.php

has anyone else had this problem? I googled it but the only things I found were people getting similar errors when they try to get into their admincp...I can get in fine and the only link I have trouble with is "options>settings".

PLEASE help....thanks.