If my digital game is installed in my library but I play the physical copy of the digital...

If the game is part of the PlayAnywhere library and is a digital copy then you will be able to install on a Windows 10 PC.

Physical copy of games is not able to be installed on a pc unfortunatly.

This is actually normal, believe it or not. The game is just a program, and most games in the market place you can download and install. But to play it you have to have a license. The license comes in two formats, either digital or physical (download
or disc). If you have a physical copy in the drive or installed on your machine, then you can get the digital version, but if you try and play the digital version without the game in the drive, it shouldn't work. You should get a message along the lines
of "If you own this game please insert disc or purchase a digital copy to play".

It's honestly why I always go digital when I can. That way I can take it with me wherever I go. I can go to my buddy's who only has a physical copy, but I can play on my account and don't have to have the disc in to play since I have a digital license
attached to my gamertag.

I still prefer a physical copy of my games.

I'm sure it stems from most gaming done on PC and wanting physical copy to be able to re-install when things go wrong. So far, with my XBox One, 2 games physical & 2 digital. The digital are the two that came with the "bundle".

I'm sure most additional purchases will be physical copys when possible

No matters what digital or physical copy, you need to have the game installed in your console to be able to play it, if its physical copy you will also need the disc, if is Digital you will need internet connection.

Better graphics, Better install times and finally a option to borrow digital games as you physical copy. (Even if i can't play the digital game when it's borrow)

Regards!