ServiceDesk Issues - Removing Additional Fields + Slow Since Upgrade

Hello ServiceDesk Support (and friends) !

I recently upgraded our copy of ServiceDesk from 7022 all the way up to Build 7506. The upgrade went without a hitch.

We have noticed now however that ServiceDesk is alot slower than it used to be with only 2 technicians logged in.

Also we have all these fields we don't even use that used to be disabled in 7022.

How can I remove the following fields?

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The extra fields are making it confusing for our staff.

Also, the performance is slow. The server it is on has always been beefy (it's one of our main web servers) but since the upgrade it takes 10 or so seconds to load a page, even longer to save the page. The server has been restarted many times, the service has been stopped and started.

Can anyone help me with this :-(

I wonder if it's time for some DB Maintenance...