Hello Pedro,
Welcome to Microsoft Community Forum. I understand that you need information if your .VOB file can be played in Movie Maker. I will assist you on your inquiry.
It depends on the Windows 8 installed in your computer. To verify if you have this codec, please try to use the .VOB file within Movie Maker. If the video did not run, kindly download the codecs that you need within the web. You can also use Media Info. Note that Media info will be able to identify any issue with missing or faulty codecs and whether it's already in your computer or not: Media Info
As for the Mediainfo, please follow the steps provided below on how to use the program:
1. Download Mediainfo
2. Install the program
3. Run the program
4. Open your movie file using Mediainfo
5. Switch the view of your mediainfo to text. To do this, click the View button on the upper left part of the window and click text
6. When you see the codec that you're lacking, please download it. You can search for the codec in **http://bing.com**
If you're still having issues, kindly convert the video to a supported format (eg. .wmv for movies, .jpeg/.jpg for photos and .wma for audio) and then add it to your Windows Movie Maker project.
Let us know the results afterwards.
Thank you.