Replacing a DVD drive in a laptop is very simple. Even if you don't have a lot of technical expertise this is something that you can do. There are no screws involved or opening up of the computer case. This is because most laptops all use modular drives that pop right out. Physically replacing a hard drive in a laptop is simple but there maybe a little bit of software work. Don't worry though doing this should take no more than a few minutes.
Get a replacement from the manufacturer. Laptops don't have big open cases that will fit any DVD drive you buy. The cases for the drive are somewhat proprietary to the manufacturer of the laptop. Call your manufacturer and give them your exact model and serial number to order the right sized DVD drive.
Shutdown the laptop and make sure it is completely powered off. Disconnect the plug from the battery and set the laptop on a flat dry surface.
Turn the laptop over. You may have to check your manual but most laptops have a button to push or slide to release the drive. Push the drive straight out and remove it from the laptop. Insert the new drive in the reverse way you pulled out the old drive.
Turn the laptop right side up and turn the power on. The DVD drive will basically be automatically found and work either fully or with basic functionality. Install any drivers by inserting the CD that came with the drive or by downloading them from the website. Installing the driver may add advanced functionality that the older drive did not have.