The banner at the top of the screen is called the Document Message Bar (DMB), it is purple for forms, and blue for certified or signed documents.
The document message bar can only be turned off by changing the program preferences. You can NOT script the DMB per form.
In Acrobat or Reader, you can go to Edit --> Preferences, Locate the Forms category and check the box "Always hide forms document message bar". Turning this off in Acrobat does not turn it off in Reader, each applications preferences are independent.
Angie