Linux

Yes, ez one (if you have installed operating systems before and know how to paste an error passage into google ) -4hours and your done start to finish. (Given you have standard hardware and don't want to set up something crazy like dual boot with raid and nas)

Moderate complexity if you have never done anything like that, plan 2-6 evenings to get it fully working with everything you need

Also: consider your scopes. For most cases Linux will just work, you just have to get used to some different interfaces.

BUT: some things will not run under linux no matter how hard you try --> google if stuff you can't live without will work

(for me I still have a dual boot windows for playing league of legends and running my vive wireless adapter, as those will not run under Linux.

For games use protonDB

I may be oldschool, but for people not comfortable around terminals I would suggest Debian KDE as it never breaks and the transition from windows is easy. You can do everything from GUI (clicky button interfaces)

For the installation of steam you might need a terminal, but there are good guides online (and you really dont need to be a wizard for that) from where you can just copy paste (when searching just add your distro e.g. "install steam Debian", and once you've got that running you can just run every game from within steam.

Since Steam has done a lot of work with proton, most games just run under Linux. In steam: Install-->play

For nearly all games not directly running, you can just force them to run with proton. It will say: "Game not compatible" in steam, you just click the gear icon on the right to open settings, go to "compatibilty" and tick "force use of compatibility layer" and select the newest proton from the drop down

The button where steam previously said "not compatible" magically turns into the blue "install" button we all know and love. And nearly all games run with only minor inconveniences (like showing keyboard hotkeys even when playing with a gamepad) or no issues at all.

You need to be aware that some games using kernel level anticheat (e.g. league of legends, valorant) can not and will never run on Linux, if the developers of the games don't add the possibility.

EDIT: for programs not related to gaming its often easier to use an alternative, if the program is not available for Linux. Most times its also more privacy foccused, open source and free

Adobe light room --> darktable

Microsoft office --> libre office

Adobe Premiere pro --> davinci resolve/shotcut

Paint/Photoshop --> gimp/davinci/dark table

Edge --> firfox

Notepad --> Kate

Fraps/relive/shadowPlay --> OBS

Etc. Pp.