In our testing, .MPEG-2 files play normally on Windows 7 with Windows Media Player 12. In these conditions, InqScribe will play .MPEG-2 files just fine.
However, we've experienced audio-only when playing .MPEG-2 files on Windows 8 with Windows Media Player 12. Since InqScribe relies on Windows Media Player (or QuickTime) as its underlying media player, it will mimic the playback you experience in your media player. So, if you're can't see any video using Windows Media Player 12, then you probably won't see any video in InqScribe.
Remember, you can always try out your media files in InqScribe by downloading it for free. This way, you can see for yourself whether or not InqScribe is the right tool for you.
Note that Windows users have the option of downloading and using QuickTime 7.
(If you're a Mac user and you're having trouble playing .MPEG-2 files in InqScribe, please refer to this article.)