AzureWinter: 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.