I have same distro of Knoppix ...,

First use webbrowsing profile, that's whats it meant for - not filebrowsing
profile --> that's for file browsing!

Second for filebrowsing- use File Manager (Super User Mode)

Third, After starting Konqueror and Control Center Start - follow this procedure.

Start up - close Konqueror and Control Center, launch Control Center >KDE Components>Sessions Manager>Check Start with an empty session>Click Apply Button>Close Control Center.

Re-Boot and they won't appear again!!!