I suspect you inserted that video as multi-slide synchronized video. Is there any reason why you didn't use event video, which will appear with its own control panel giving control to the user?
You cannot pick slides to show the playbar, you either show it for the project or not. It is however possible to hide the playbar by using the command 'Hide Playbar' which can be triggered by the On Enter event of a slide. Since the real estate needed for the playbar will remain, it will take on the color you specifyfor the Bottom border in the Borders tab of the Skin editor. Playbar will remain hidden until you show it again with the command 'Show Playbar' by the On Enter event for the slide where you want to use it.