Another vote for Debian, and I’ll suggest you go ahead and install Jellyfin directly rather than messing with Docker.
jellyfin.org/downloads/server
I’d been running JF under Docker on my NAS, but when I moved to a new server I decided to just install it directly and it hasn’t been any problem at all. You’ll get a notification when it needs to be updated and it’s just a few clicks to do so. You won’t have to fight with Docker to get hardware acceleration working - which isn’t to say it won’t be a PITA, but it’s one less layer of complication.