Well your system's Hardware requirements are fine for the software there is no need to upgrade the hardware of your computer. But you never mentioned from which website you trying to download the software because some website's have broken links with their downloads just follow this link to download your software –
https://quake-2.informer.com/download/ after successful information and downloads close all the applications and restart your computer and then install this software and then after complete installation restart you PC again that your computer can be configured automatically for the compatibility of this software. While there is another option for you just copy all the data of CD to your computer and then try to install after restarting your computer it will work.
It means that your system needs the CD while playing the Quake 2 game. You need to look for a no cd patch for your Quake 2 program to run without the CD so that many users can also use the CD. Don't even think about removing your Quake 2, that is the only problem that you have.
Many games are actually like this and the above are solutions for each and every game that you run with the use of CD and then got an error when the CD is not there.
Unfortunately, you did not include what operating system it is you are using. If you are installing the game “Quake 2,” the problem could be the operating system. The game “Quake 2” is quite an old game. Before you install it, make sure your computer meets the requirements. “Quake 2” supports Windows 95, Windows 98, and Windows NT.
But according to Steam, the game is very much compatible with Windows XP and Windows Vista. The game requires 90 MHz Intel Pentium or equivalent AMD Athlon or faster processor, 16 MB RAM, video card with 256 colors, sound card, 25 MB free space, mouse, and keyboard. Multiplayer session supports both local area network and online connections and supports up to 32 players.
If you are using either Windows XP or Windows Vista and the game does not install, try installing it using compatibility mode. Start Windows Explorer then navigate to the location of the setup file. Right-click on the installer then select “Properties.” Go to “Compatibility” tab and check “Run this program in compatibility mode for” and then select “Windows 95,” “Windows 98,” or “Windows NT.”
Click “OK” then double-click the installer to start the installation. See if this works. “Quake 2” is an action game developed by id Software published by Activision released on November 11, 1997.