How to make my system adapting itself to the customer's screen resolution ?

Of course, there is the ScaleBy method and the like but what happens with
the MessageDlg dialogs?

Is there a way to scale them too ? Also, I have a problem with the main menu
of my Main MDI form. The character size is not scale while the character
size in my chid forms are.

Any hint would be appreciated

Tks

JM GALLIOT