Customizing User-Interface

[CryoGenID]

Hey you all!

I'm currently trying to figure out which Windows-Based-System to use (Plesk or Ensim pro) and while evaluating Plesk I've collected some questions...
Today I'll only ask the most important one, which is the customizing of the user-interface.
I don't want my customers to see all the informations displayed there, as well as some buttons have to be removed.
Can I realize that? If I'd create a theme of my own(can I do that ?!), could I put only the buttons and informations i want to be displayed into that new theme?

Thanks already a lot in advance for your help!

Yours sincerely,

Christian