How to Play a DVD-R on an iMac
A DVD-R disc is the most common type of blank recordable DVD disc that a computer user can use. You can play DVD movies on DVD-R discs on your iMac because its DVD drive and software are compatible. Use the iMac's default DVD Player application to play a DVD-R disc. The procedure is straightforward and nearly identical to using a standalone DVD player.
Insert the DVD-R disc in the side slot of the iMac. Wait for the icon of the disc to appear on the desktop.
Double-click the "Applications" folder inside of the iMac's main hard drive to open it. Scroll down to the icon of the DVD Player. Double-click on the DVD Player's icon to launch it. The player may launch automatically when the computer recognizes the DVD in the drive.
Click the "Play" button on the DVD Player's control panel. You will also see all the usual controls, such as fast forward, pause, etc. Click the "Stop" button when you are done watching the video. Click the "Eject" button on the control panel.
Click the eject button on the DVD Player to eject the DVD-R, or drag the disc's icon to the trash.