|Turn off system. At boot try the eject button on the drive. |
Turn off system.
Gently pry the tray open. There is normally a cover that might pop off. In the center the tray is generally able to access.
If the DVD has shifted or broken apart you might just be out of luck.
"Best Practices", Event viewer, host file, perfmon, antivirus, anti-spyware, Live CD's, backups, are in my top 10