|The DVD is not working...is it damaged or does it not boot from the DVD drive? If the latter then you need to go into your BIOS and change the boot order to do you DVD drive before the HDD. |
(How this is done depends on your computer because every computer is different. Need to know the Model and manufacture to help further.)
If you are not good with computers, I always recommend you seek out some help because this is not an easy thing to do a system restore because you can make things worse.