2 different GTA V disks won't install, and why can't I just download the game digitally...

You can download the game digitally using the Xbox app on your mobile device, then once the game has downloaded, you can put the disc in the console and start the game. The disc will just be used for licence purposes.

installing disk 2 [the disk you put in to actually start GTA V] will hinder game performance, so don't install disk 2 if you want quality performance...but disk one is the manditory install

No once dlc is redeemed it is tied to your gamertag, you cannot give it away once redeemed. If you have still got the dlc in code form on a card and have "NOT" already redeemed said "CODE" you can give that card to your friend then he or she can redeem and
download it. If the GTA V game is in disc form you can give him or her the physical game. If the game is in digital form you cannot give it away as it is also tied to your gamertag (if downloaded from games on demand) If you installed the game from a disk
to a hard drive or USB stick it is tied to the physical game disk.

To put it simply if you wanna give your friend GTA V, give them the disk to keep. If the downloadable content is already redeemed you can't give it away. If GTA V is a games on demand version you cannot give it away either.

Hope I helped

Hi Quentarus, I know it can be very frustrating when a game you pay money for doesn't want to work. Try this, this has been known to fix issues with disk error messages for digital games. Ok try deleting GTA V, then download some demos that add upto the
size of GTA V, in this case we're talking about 12gb with the extra packs installed. Once you have done that, then redownload GTA V, hopefully the problem will be fixed. Let us know if it helps.

To me, there are three major factors:

1) Are you concerned about bandwidth? If so, disk option is better as it installs some from the disk, and only downloads the updates. (As opposed to downloading the whole game)

2) Are you concerned about the ability to sell the game later? If so, disk is the way to go again because you can't currently sell your digital games.

3) Are you concerned about the ability to loan your games to friends? If so, again disk is the way to go

If none of the above are a concern, then I recommend purchasing digitally as both options consume the same amount of HDD space on your console, but if you buy digitally, you can quickly switch between games without changing disks.

Personally, I digitally purchase games that I know I will come back to again and again and never want to sell. (Like GTA V and Titanfall) And games that I know I will play through and never touch again, like Watchdogs, I puchase on disk so I can sell them
after I'm done with them.