Very much depends what format the file is Gerry as it likely needs to be converted. Plenty of free progs around to do that if it isn't something obscure and easy enough to write to DVD after that.
If you write straight from SD card to DVD all you'll do is copy the file which may or may not be playable. presumably you want to view on a TV?
Bob
ps Look at the properties of the file on your 'puter.
Did your camera not come with editing software?
Edit:
Just looked and probably mpeg 2 ps in which case easy enough to convert to avi or mpeg 4 then use standard copying software ( I use Nero burning rom 10 but plenty available ) to write as video to disk - don't just copy the files!
One piece of good advice that I read years ago....... whether photos, audio or video, always work on a copy of the original. If anything goes wrong you can delete the copy & make another from the original. If you only have the original & it goes wrong, you have no back up.
I just created a basic DVD with menu using DVDstyler, which was a free download and pretty easy to use, there were youtube tutorials but I didn't need them. The DVD looks good and works in a standard player.