I assume when you go to my computer you no longer see your DVD drive in your available drives.
First go to my computer, properties, hardware, device manager and see if you can see the DVD drive there.
You can disable the enable the device there, Check my computer for the drive again.
If not you may have to reboot. Go the the setup options and restore the factory defaults. This usually restores access to your drives. WARNING: It also undoes any custom settings you have have had. Document your settings before you do this. Otherwise you may have an even bigger problem.