are you meaning a custom screen in WD set up as a signature banner?
you can reset a custom screen in WD
or if you are meaning the signature banner via the summary image and icon setup
then when you say start over, do you mean for the colours you have selected, background image, etc etc?
if so, then run regedit.exe,and find wdisplayftp.ini, then delete the key
[Signature banner]