http://windows.microsoft.com/en-CA/windows/dvd-playback-help
Please read the excerpts below:
The Windows DVD Player app is available free for a limited time for people upgrading to Windows 10 from Windows 7 Home Premium, Windows 7 Professional, Windows 7 Ultimate, Windows 8, or Windows 8.1
with Windows Media Center.
To be eligible for the free DVD Player app, you must upgrade your Windows 7, Windows 8, or Windows 8.1 PC rather than perform a clean installation.
If you’re running an edition of Windows 7 or Windows 8 that doesn’t include Media Center and you upgrade to Windows 10, go to Windows Store to buy Windows DVD Player or another app that plays DVDs.