Hello mrbean,
There are a number of decoration controls in LabVIEW that can be used to customize the appearance of a VI. I believe it is one of the lowered or recessed boxes that are used to hold the front panel components you are referring to. You should be able to find the decorations palette under the All Controls palette or Modern palette depending on what version of LabVIEW you are using. I hope that helps.
Regards,
Marty H.
National Instruments