I keep forgetting to mention this, so here it goes. :) I wrote my dissertation in LaTeX/TeX. Which, as any sentient mammal knows, is the best system for writing papers and scientific documents ever concieved in the history of the universe (it's good for everything else too).

Okay, maybe I exaggerated a little bit. But I do like it a lot. :)

Anyway, the editor I've used throughout these last couple of years has been WinEdt, an excellent, excellent LaTeX editor which integrates seamlessly with MikTeX, IMO the best LaTeX/TeX distribution for Windows. If you must use Windows and need a good LaTeX editor, the MikTeX/WinEdt combination can't be beaten.

ps: and is the TeXbook a great read or what? :)