I personally prefer Debian based distros just because of the number of apps in the software repo. Probably consider Ubuntu or Mint in your case. My wife and I have used Linux pretty exclusively for over 20 years. Ease of use is not that much of an issue once your setup. My wife and her dad are not technical and they have few issues.
Installing, and fixing issues is more technical but it is for Windows too especially if you do not get it preinstalled. You presumably have some stratagy for Windows support. Linux same, have a stratgey for it.
Reguarding apps, you said typewriter, movies, music, games. Office suite look at LibreOffice. Movies and music if it is online just Firefox or any other browser you choose. Firefox is good at working with PDFs too. Any distro should come with a document viewer, photoviewer, video player, and music player. You can choose from tons of other or more advanced tools. Debian for example comes with over 60K packges and Ubuntu and Mint are similar. There are also 3rd party sources too. Flathub or Snapcraft for example if you want something not in the repos.
If you go with a Debian based distro with a lot of apps in the repos, you probably my not need these other app souces, but some people like smaller distros, something special just not in the repos, or a newer or different version of app. For example I use Joplin which is a notes app that is not in the Debian repos.
For apps finding an app name and starting links https://alternativeto.net/ is your friend. For distros, https://distrowatch.com/ is your friend. Strongly favor a distro in the top 10 on distro watch unless you have some special need.
Edit: You will notice that the top 10 are all Debian, Arch, Fedora, or SUSE based in that general order of more to less popularity. Linux distros tend to be based on these base distributions. For example Mint is based on Debian and so is Ubuntu.