Windowed breaks immersion heavily (it’s a tiny 640x480 window on a 55" display for me), and I apparently click off the edge frequently-enough to make windowed virtually unplayable. Limiting yourself to windowed is a bad experience, and that mode is mainly only good for the instant load times for testing 
My vote goes for nGlide; it’s simple, and integrates better on modern Windows with DirectX or Vulkan modes instead of OpenGL. It’s a general Glide wrapper, and I compared it with Sven and dgVoodoo recently: Real classic Diablo 2 from a guy that’s played since day 1 - #29 by Espionage724-1903
Sven’s wrapper specifically left Game.exe running in the background on game exit, whereas dgVoodoo nor nGlide do that. And although Sven’s works fine, I know Intel’s OpenGL implementation on Windows isn’t great and like DX through nGlide better.
dgVoodoo I think is a great option for people wanting to switch between fullscreen and windowed!