Hundreds of error 28 messages

[Frank Woolf]

My hosting company recently updated my vBulletin to the latest version. I tried accessing vBulletin options in the Admin panel and got this error:
Database error in vBulletin 3.5.1:

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 : Got error 28 from table handler
Error Number : 1030
Date : Sunday, November 27th 2005 @ 11:35:45 PM
Script : http://motorcyclephilippines.com/for...ons.php?null=0
Referrer : http://motorcyclephilippines.com/for....php?do=modify
IP Address : 210.213.196.141
Username : Frank Woolf
Classname : vb_database


Then I started getting hundreds of error messages and nobody can add attachments to posts.
I am using an SQL manager to try to repair the database but have been waithing for it to finish for hours.

One of the error messages:

Database error in vBulletin 3.5.1:

Invalid SQL:

SELECT pm.*, pmtext.*
, icon.title AS icontitle, icon.iconpath
FROM pm AS pm
LEFT JOIN pmtext AS pmtext ON(pmtext.pmtextid = pm.pmtextid)
LEFT JOIN icon AS icon ON(icon.iconid = pmtext.iconid)
WHERE pm.userid=9247 AND pm.folderid=0
ORDER BY pmtext.dateline DESC
LIMIT 0, 50;

MySQL Error : Got error 28 from table handler
Error Number : 1030
Date : Monday, November 28th 2005 @ 03:34:31 AM
Script : http://motorcyclephilippines.com/forums/private.php
Referrer : http://motorcyclephilippines.com/forums/private.php
IP Address : 210.213.145.155
Username : raptor_1108
Classname : vb_database

Can anyone tell me, in simple terms, what I should do? Many thanks