Diz, Bonk will likely be using the MYSQL admin control panel in Start>All Programs>MYSQL>MYSQL Administrator
To access that you'll need the username and password. Once in a new window will open with various options.
One option will be catalogs. Click on that and you will see the database he's using for the server although he may have more than one db in there so you'll need to know what he named it. If you see it in there and know the name all is good so far. The default name or name in the FAQ is "dynaverse" but he could have named it something else like forge. If you don't know the username and password or he doesn't use the admin control panel then you're kind of stuck.
Bring the server down.
Select the option above catalog called Backup. Click New Project to open up the fields so you can give the backup db a name. Click on the db that you want to backup and click the arrow key >. The field on the right will populate with all the tables. Click the Execute Backup now and save the file somewhere handy and memorable. Note, this will default to where he last saved files to so it's handy to remember this location.
Next you will need to create a clean db. If he's using an unmodded standard OP mysql db I can send you a file. He may already have one anyway and you can check by doing the following:
Between Catalogs and Backup there is the restore option, click on it. Then click on Open Backup File. That should default to where they are saved to. I don't know the naming culture he would use but maybe there is one there created at the date the server started it will be about 18kb in size. Once you select the right one, click Start Restore.
Now that db is the Live one. Close the Admin window and restart the server. Cross your fingers and pray to whatever deity you worship and take cover.
If there is no database saved from previous then you could use the one I have sent you via email but if he has added custom tables some elements may not work - perhaps he added some for OCI I really don't know so it's likely that the webpage may error though the server itself will work fine.
edit: If it all goes Pete Tong, shut the server down then use the restore option and select the file you backed up earlier.