Need Some Advice - want to tidy up the data bases for security issues

[Damien001]

We had an issue with one of our members of our web team leaving, he left behind a script that gave him access to our databases.

To be safe we want to downgrade all user to visitors regardless what user-groups they are (except for super admins)

We also want to make sure that no user has any set permissions attached to their account to give the access (i.e. access for single users not based off user group access)

What we want to do is to wipe the forums (the files) and installing a clean copy, we want to then use the old database but we only want to keep user (all converted to 1 user-group), private messages, forums and topics/posts; everything else user-groups, access settings/permissions. To sum it up anything that might give anyone permission to our forums removed.

We also re doing our user groups completely

Any tools/mods or advice would be good

Is there an tools or mods that would help with us doing this

Thanks

Damien