[Disc Auto-Start] is an option under Settings > [System Settings] that lets you set whether or not automatically to start a disc when it is inserted.
Disc Auto-Start

[Disc Auto-Start] can either be set to [Off] not automatically to start the disc, or [On] to start the disc automatically .
When set to [On], if a disc is inserted when the power is turned on the disc will automatically start.
Even when set to [On], a disc will not automatically start in the following situations:
- When another operation is being performed under the Home Menu
- When a CD-R or another type of data disc is inserted
- When there are multiple users and automatic login has not been set