As a first step, see if you can get by by just using FOSS software on Windows. If you can, then you will lose nothing, swapping your "app launcher" is inconsequential if the programs you use are the same.

Wine/Proton are very good when it comes to game support, so you should be alright there. You can always check protondb and winehq to confirm the support status of the game you want.

I recommend a boring and stable distro like LinuxMint. It is based on Ubuntu but even better imho.