Hi,
1. Which Operating System are you using?
2. Were there any changes or updates made on the computer?
3. Are you able to play the DVD by cancelling the error message?
4. Is the issue confined only when trying to play this DVD?
Try to play the DVD on a different computer and check.
The Xerces.dll error message may be caused by Windows system corruption.
Refer the link to use the System File Checker Tool (SFC) to troubleshoot missing or corrupted system files in Windows 7.
SFC /scannow is a super-useful command you can use in any Windows version. When the SFC (System File Checker) command is used with the /scannow switch, the tool will scan all of the important Windows files on your computer and replace them as necessary.
Missing and corrupt operating system files (like many DLL files) are arguably the biggest cause of major Windows issues. Considering that, plus the fact that SFC /scannnow is completely automatic and very easy to use, the tool should usually be one of your first troubleshooting step.