Hello and welcome to AndroidCentral. You can plug your phone into your PC with the USB charging cable to transfer your files. Depending on what version of Android you have, you may need to put the phone into USB transfer mode, but it should tell you that as soon as you plug it into your PC.
Assuming you have a Windows PC open your explorer and you should see the phone as a removable media disk. Open the phone folder and your video should be in the dcim directory. Just drag and drop it to a folder on your computer. From there you can put it on a DVD or other removable media.
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