It's the Doom Shareware and FreeDoom. What more do you want ? Actually, Freedoom: Phase 2, FreeDM once deathmatch comes, Lastermaul (Free replacement for Hexen, similar to Freedoom), Blasphemer (Again, same but for Heretic).
The menu controls are a bit confusing too but it's doable, surely due to s&box limitations.
Thought, even if Windows 98 is abandonware, you should probably edit that web port of it with a made-up OS. Just sayin'.
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