So I am considering buying the GOG version of Deus Ex, due to all the trouble I have had getting my disc copy not to run, but to work properly.

I have already tried several things like the launcher mod, as well as the new vision mod which didn't help.
I could list all the problems I was having, if necessary.

But would this version run straight away after downloading?

If you can explain what problems you've had, I can try to help you figure them out. I've got plenty of experience getting Deus Ex to run.

As for your question: This is the Game of the Year Edition as it was on disc, pre-patched to v1112fm.

I see.. my install was from GOTY disc.

Let's see, I should be able to recall them all.
Biggest problem being the texture or shading was extremely off.
Shadows would go from black, to purple, to lighter purple up until the spot where it was well lit. It wasn't a gradual transition, but sectioned off by shade.

The big thing that made me look and go "something is very wrong here" is when I entered the vent system in the statue of Liberty. In the dark it looked very... green, and muddy. The dark of the vent was a very ugly muddy green, not pitch black. Plus you could see the black spots all over, marking the varied texture that the vent has if you were to see it lit up.

The other thing is that model for the GEP gun, it kind of overextended when I had it rquipped, to where I could see the part of the model was missing, that would normally be off screen.

Okay, so a renderer? I don't recall if I used a renderer the first time... this was way back in September that I did all this.
What I do remember using was the New Vision Mod. That did absolutely nothing.
I followed the video guide to installing it too, and still didn't work..
How do I know which renderer is best to use?

Yeah, the view model goes too far.
Um, I am not sure what aspect ratio my monitor is, how do I find that out?
I can tell you the resolution, which is 1920x1080.

You choose a renderer when you run the game for the first time after installing, and when you select "Rendering Device..." from Settings-->Graphics. Normally, your options are Direct3D, and Software Rendering, plus other "unsafe" options which you have to check a button to see. When you installed New Vision, it would have also installed Chris Dohnal's updated OpenGL renderer, but you would have needed to set Deus Ex to use it manually.

As for which renderer is best, I would go with the OpenGL one. Alternatively, the author of the Deus Ex Enhanced mod has one for DirectX 10, if you have a Windows Vista or Windows 7 computer. I can't speak to how good that one is as I still use XP.

As for your monitor, 1920x1080 is 16:9. You'll want your FOV set to 85, I believe, for that. Kenite's launcher includes options to set that automatically.

You know maybe I did try a renderer, cause OpenGL sounds rather familiar, and I do remember an applet where I had to set a few fields.

I am using a Windows 7 PC.

So should I make sure to download and get the renderer ready before I run the game for the first time?
Okay.. so Kentie's launcher?

I know what things I need... I juust have no idea on the proper way to do them in order and get them all working.

Plus I gotta make sure I uninstall and get rid of everything I did before, I never bothered uninstalling the game.

Kentie's launcher supports most of what you need.

* Kentie also has a Direct3D 10 renderer.
* Kentie's launcher replaces DeusEx.exe
* Kentie's launcher allows you to choose your rendering device, resolution, FPS limit, whether or not the UI scales with resolution, color depth, and field of view setting. It also makes it easier to set up your mods, although I haven't yet used it for that purpose.

What is the proper way to install everything and get it working?
Cause I know I've used one of these before.. but nothing in it worked.

You'll want to check emualynk's mod installation guide.
http://www.gog.com/en/forum/deus_ex_goty_edition/deus_ex_augmentation_guide

Do I have to use ALL those mods though?

Really, I just want to play vanilla and have it not look like crap XD.
Can I just do steps 1 to 3, and call her good. Maybe go back and finish later if I want to?

Yes, Steps 1 to 3 are all you really need for a basic install. If you can get it working right, New Vision will improve the look of the game dramatically, though.

In my experience, at high resolution and in widescreen, the GEP gun model ALWAYS gets cut off, by which I mean you can see where the right-hand side of the model ends. This is true even if your FOV is correct. This is because the GEP gun model is supposed to overlap the right-hand side of the screen, but if your resolution/FOV is wider, the screen extends past it.

Regarding the graphical problems, you can choose renderers straight through Kentie's launcher. Try options you haven't before, starting with Direct3D and then maybe OpenGL, or downloading Kentie's D3D10 renderer from his site if you're on Vista/7.

I had problems with the game running way to fast once. but i installed it again later, and it ran fine. I'm not using the GOTY version, but the original version.