Create a simple menu based DVD - delete the default background (or not), and delete the default text heading. Drag the movie onto the menu, change the button style to text, delete the text in the button and set the active and selected color sets to transparent/none.
I'd do like Scott says, but add a background with the company logo or the name / date of the meeting. Maybe even the meeting's agenda, if several topics are being covered. Executives like crap like that. ;-)
If the panasonic deck goes into screensaver/jumping-logo mode whilst a static menu is playing then make the menu do something but have nothing on show or to be heard in it. ie It could play black video or have a black motion menu item on a black background.
Making the play button start the movie (as opposed to OK instead) will be more effort than perhaps it is worth.
Otherwise skip the DVD player and use one of the old SigmaDesigns Hollywood+/netstream2000 cards to give you playback in that room. You could play from the network without needing to burn a disc and you'd get good interlaced video without resorting to a TV-out from a PC interface - which is often lacking in resolution after the de-interlace process that daftly has to be done for most/all players.