To convert a DVD video to an MP4 video with VLC Player, follow these steps:

1. Insert the DVD into your computer’s DVD drive.
2. Open VLC Player on your computer.
3. Click on “Media” in the top-left corner of the VLC Player window.
4. Click on “Convert/Save” in the dropdown menu.
5. Click on the “Disc” tab in the new window that appears.
6. Make sure the “Disc Device” field is set to the correct DVD drive.
7. Check the “No disc menus” box to skip any DVD menu screens.
8. Click on “Convert/Save” at the bottom of the window.
9. In the new window that appears, click on “Browse” to choose a location to save the MP4 video file.
10. In the “Profile” dropdown menu, choose “Video – H.264 + MP3 (MP4)” or “Video – H.265 + MP3 (MP4)” depending on which codec you prefer.
11. Click on “Start” at the bottom of the window to begin the conversion process.
12. Wait for VLC Player to finish converting the DVD video to an MP4 video.

Once the conversion is complete, you should have an MP4 video file that you can play on your computer or mobile device.