Okay, I'm back from my trip but somewhat tired so I don't think I will get much programming done today. However, just before I went on my trip I got Doom to actually run in DS2x86! One milestone reached! It does not play any sounds yet, which makes it not all that immersive or even playable yet, but it does run and it is possible to evaluate the performance of my protected mode 32-bit emulation with it. Doom runs only at a marginally playable framerate using the default settings, which is not all that unexpected considering that the emulation speed is only about 25MHz 486. I remember when I had a 486/33 machine and played Doom against a friend who had a 486/66 machine, and I usually lost simply because I had a slower machine. Things improved when I also got a 486/66 machine. However, some settings in both DS2x86 and Doom can be adjusted to make it run better, and the best settings I have found so far seem to be the following:
* DS2x86 CPU speed at 396MHz
* Screen mode Zoom (so the smooth interpolation does not take CPU cycles)
* Screen refresh at 15FPS (so the emulation gets more CPU cycles)
* Doom Options: Graphic Detail: Low
* Doom Options: Screen Size: Less than maximum

Source- DS2x86 Blog