Database entries not displaying

What database version are you using??

If it is access make sure you have the database outside of your web root where it can not be downloaded or over written through a web browser.

Make sure that all admin and moderator passwords are changed and difficult to guess.

Make sure that someone hasn't accidently overwritten the database through FTP with an old back-up copy.

Access often becomes corrupted and does loose keys etc. a compact and repair on the database may sort out the problem.

Lastly, if you are using Access, DON'T switch to MS SQL Server which is much more secure, handle more connections, and doesn't get corrupted all the time like Access.

For most of your forums the drop down show topics list is set to show topics posted in the last week.

If you change this to 'All' you will see all the topics in that forum.

The default for the drop down list for each forum can be set in the admin  area for each forum on the forums setup page where you set forum title etc.