My installation from a week ago was a bit interesting, because I received a message saying I couldn't install from the disk, because it would be incompatible. What I did is just copy the baseq3 folder from inside the Quake3 folder and installed the latest patch, and that gave me everything I needed. After reading your post though, I decided to give it another shot and install from my disk again, but I noticed a second setup.exe I could actually run inside the Quake3 folder, so at the time of this writing I am installing from the disk. I'll post the results tomorrow since I don't have any time to test at the moment.

Attached is an image of the message I get when I install from the disk through the setup.exe outside of the Quake3 folder.

After attempting many different ways of installation, it seemed that running the setup from the disk in winxp sp 3 compatibility has given the best results, although I do suffer from occasional frame drops and it even freezes up completely at times. It also helps to run the game at r_mode 3, which looks wonderful on my 1080p monitor. Regardless, it seems that I can't find a way to improve it anymore, at least the game is somewhat more playable than it was before. Thanks for the help dudes.