Jellyfin has locked up my server. Should I reboot or wait?

I started the scan for my movie collection (roughly 140 movies) on my Raspberry Pi 3B. It has become unresponsive and I can't ssh in now. It seems to be due to all the ffmpeg instances. I have two questions:

Should I wait for an hour or should I just reboot the server? Also, is there a way to disable the setting for chapter images from the web UI? I can't find it in the setting.