Did you enter your username here?
http://www.vbulletin.com/members/vbulletin.org.php
If so, try this link:
https://vborg.vbsupport.ru/register....n=requestemail
Also post the original error message (from db_mysql) and the error your are getting from repair. Right-click on the error page and go to View/Source. Then cut-n-paste the error message here.
Note we will be unable to help until you've verified you are a valid license holder.