Welcome to the Dell Community  @lankykate 

Two things you may need???

1. VLC Media Player (64-bit)

https://download.cnet.com/VLC-Media-Player-64-bit/3000-13632_4-75761094.html

2. Windows 10 Codec Pack:

https://download.cnet.com/Windows-10-Codec-Pack/3000-13632_4-77498091.html#full-specs

Best regards,

U2

You need actual DVD playback software installed on your PC.  Windows used to support that natively but it was removed at some point, I guess because Microsoft didn't want to pay the licensing fees necessary to include that in Windows.  VLC is a good option since it supports DVD playback and is free (because it uses an open source library that basically hacks through the encryption rather than an official license).