@admitsWrongIfProven As far as I remember Arch comes with systemd and indeed it does start services; you wouldn't expect internet connectivity otherwise.
Anyways, you have the same amount of control in ubuntu: you can remove stuff and you can disable services. The difference is pretty much in the package repositories.
Don't know exactly about the video encoders, but packages are more or less the same as the ones in ubuntu. Probably you have to enable non free software packages.
Arch has non free software packages by default.

If I must say, the biggest advantage of Arch is the availability of the AUR, which makes niche software easier to install.

If this is a computer you need to work on, I strongly advise any Linux distribution but Arch. Troubles sometimes arise with Arch, and you don't want to be troubleshooting for a couple of hours on a friday afternoon because you have to complete a presentation.