A DVD-video playback apparatus including a navigation manager that estimates the size of each title included in a DVD disc when the navigation manager receives a playback start command for the DVD disc from a main controller. The navigation manager sets titles whose sizes are larger than half of the size of the largest title as monitored titles, and starts playing back the DVD discs 1 by controlling a presentation engine. When the playback of all of the monitored titles is completed, the playback is stopped and a disc-change request is issued to the main controller. The main controller changes the DVD disc to another DVD disc by controlling a DVD changer, and issues a playback start command for the new DVD disc to the navigation manager.