This isn’t really the usecase, you’d be better off just playing it with VLC from a BD/DVD drive with the menu plugins. Netflix won’t have DVD menus either. Ripping is necessary for this to make your physical copies accessible via Jellyfin. May want to check ARM (Automatic Ripping Machine) to streamline the process. Legally, this is perfectly fine in most jurisdictions, because you are creating a backup of your purchased property.

Adding to this (which is a solid recommendation and answer BTW), you can try out podman kube play <your-file>.yaml (see here) before going full k8s or k3s setup to familiarize yourself with the concepts, without moving too far away from the docker-compose ease of use.

Regarding question 1, any distro works, but if your are looking specifically for a lightweight, fast to deploy node host os, I recommend opensuse microOS/leap micro or similarly, fedora coreOS. With both you can drop a combustion/butane/ignition config file in a usb installer partition, so you can quickly integrate fresh installs in your cluster (ssh, network config, user accounts, package installs) see https://opensuse.github.io/fuel-ignition/

To be fair, many roombas have a mini DIN connector somewhere, which opens up the possibility for external control - what I plan to do when mine stops working due to server shutdown. However, getting replacement parts will get more and more tricky as time goes by.

I just had to through out a mostly functional airfryer because the drawer rail disintegrated and the replacement part is no longer manufactured. The oldest one I could get was a “new” version with more plastic and a slightly bigger size, so it didn’t fit by about 5%.

It really should be illegal, there is no logical reason for 500 slightly different models and inoperability of basic functions (drawers, APIs, …) aside from malignant greed and planet destruction.