Hi Ronda P,
Welcome to Microsoft answers!
a) Which edition of windows vista are you running on the computer?
b) How exactly are you trying to burn the DVD? What file format are you using?
I would first suggest you to save the project on your computer and then try to burn to a DVD at a slower burning speed.
Choose a slower burning speed for your DVD burner by doing the following:
1. Return to the Add pictures and video to the DVD page, and then click Options.
2. In the DVD burner speed box, select Medium or Slow.
Change-Windows-DVD-Maker-DVD-Video-settings
http://windows.microsoft.com/en-us/windows-vista/Change-Windows-DVD-Maker-DVD-Video-settings
If the issue persists, download service pack 2 for windows vista on the computer
How to obtain the latest Windows Vista service pack
http://support.microsoft.com/kb/935791
See the link below:
Error message when you try to publish a movie to a DVD by using Windows DVD Maker in Windows Vista: "Unspecified error"
http://support.microsoft.com/kb/949281
For more information, please check the links below:
Burn-a-DVD-Video-disc
http://windows.microsoft.com/en-us/windows-vista/Burn-a-DVD-Video-disc
Troubleshoot-problems-with-creating-a-DVD-Video-using-Windows-DVD-Maker
If you are using windows media player, see the link below:
Burn-a-CD-or-DVD-in-Windows-Media-Playerhttp://windows.microsoft.com/en-US/windows-vista/Burn-a-CD-or-DVD-in-Windows-Media-Player
Thanks and Regards:
Ajay K
Microsoft Answers Support Engineer
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