what a complete instalation will look like
1: A complete installation of the game is what you get in the first post of this thread.
Either the "Base Game + Crack", or the "Skunked" version. They're almost identical except the "Skunked" version is a smaller file size, made by one of the forum members kindly reducing image quality for smaller picture sizes.
2: Play without mods. There's a thread dedicated to gameplay questions.
3: Advice of what mods to get is purely subjective, since not everyone likes that same mods.
There's a couple of "Super Mods" that are collections of different mods together.
If you're interested in ones that continue the story, there's one called "Untold Stories" that does that, but it's still best to play without mods for a first time through. Especially for when you reach the end of what's officially available as far as content goes.