Crash generating movie plugins

Disabling the Movie plugin's thumbnails will make Opus fall-back on the Windows shell for video thumbnails, so you shouldn't lose the thumbnails entirely. If that prevents the crash then it may be all you need to do.

If you want to get the Movie plugin generating thumbnails again without the crash, the issue is probably a video codec or splitter which is crashing either all the time or when asked to extract frames out of certain video files.

The Enable/fix playback of various media formats in Opus guide has some suggested codecs & splitters which have worked well with Opus in the past (although it's always possible they'll have updates/versions which don't, of course). Trying those would be what I would do. (Unless you know that you've installed some other video codecs or codec-packs which you no longer need; uninstalling them may also cure the problem.)