First, make sure you followed the installation instructions correctly. If you are unsure, select a debug build in the Launcher, run it until the pilot select screen, and then post the fs2_open.log from your data folder here.
- Enable [All features on] in the [Features] menu
It's generally better to pick and choose the features you want.
That said, the following features will enable all the graphical goodness:
"Enable specular"
"Enable glowmaps"
"Enable environment maps"
"Apply Lighting to Missiles"
"Enable normal maps"
There are a few others you can enable, but they're mostly matters of personal preference, like the 3D shockwaves or the 3D radar.
I would also recommend "Use models for ship selection", "Use models for weapon selection", "Enable 3d warp" and "Enable flash upon warp", but again, those are a matter of personal preference.
Further customization options can be found here:
http://www.hard-light.net/wiki/index.php/Sample_Lighting_Settings- Load the [mediavps] folder in the [MOD] menu
Definitely.
- Enable [Direct3D8] and [General Settings] to [High] in the [VIDEO] menu
Nope. Selecting Direct3D has no effect whatsoever, as the engine is OpenGL
ONLY. "General settings" should indeed be set to high, though.