To get into the In-game settings screens, press the Options button from the main menu. Beneath it you'll see four buttons appear: Controls, Customize, Video and Sound. Once you've created/loaded a profile you can change these settings. Each is covered in detail below:
Here you can assign keys/buttons to each function, from the common settings through to vehicle-specific ones. Make sure you remember to press the little arrow at the bottom of each box to see the 2nd page of commands. Also note that the Mouse (keyboard) sensitivity and Invert mouse settings are separate for each function. That is, your Air mouse sensitivity settings can be set differently to your Infantry mouse sensitivity settings. The further to the right you take the slider, the more sensitive your mouse to movements. If Invert mouse is selected, moving your mouse forward will look/move down and pulling it back will look/move up.
Once you've finished assigning all the settings don't forget to press the Save button.
This screen will allow you to configure the on-screen settings for your profile. These are shown below, with performance impacts noted:
Playername - This is the name displayed for your character to other players and in the player listing screen.
Tooltip - With this setting selected you'll see hints and tips whenever you go near certain items or perform certain actions. This is useful if you're new to BF1942, but for most people this should be unselected. Leave it off for a slight fps improvement.
Radio Tooltip - If you have the Radio command buttons showing at the top of the screen (toggle them off/on in-game with F8), selecting this option will show text under each radio button. Turn it off for a slight improvement in fps, and while you're at it, turn off the Radio buttons themselves for an fps boost.
Static Minimap - With this selected, the minimap in the top right corner will not rotate as you turn around. Unselecting this option will allow the map to rotate. No impact on performance either way.
Minimap Transparency - Determines how transparent the minimap is against the background. I recommend a high level of transparency (i.e. around 20%) so you can see the whole screen. Has negligible impact on performance.
Crosshair Color - Determines the color of your crosshair. I recommend choosing a color which stands out from the background to help your aim. Has no impact on performance.
Again select the Save button to lock in your changes.
Video Performance - Ignore this box. Don't use the pre-set performance levels, as you can achieve better results customizing the settings below.
Display Mode - This allows you to choose the resolutions, color depths and frequency your graphics card/monitor combination supports, e.g. 1280x960[resolution] x32[color depth] @ 85[frequency]. Resolution is important in determining how clear the picture is on your screen - However the higher the resolution, the lower your performance. The color depth can be set to either 16-bit or 32-bit, with 16-bit being faster. I highly recommend 32-bit as not only does it give richer colors, 16-bit color is known to cause issues at times with flickering textures. Finally, the frequency is the number of times per second your monitor screen refreshes itself - the higher the better. If you can't see Frequency, or it's set at 60Hz for all resolutions, see the Advanced Tweaking section for the fix.
Graphics Quality - There are three settings on this slider: Low, Medium and High. The higher the graphics quality the more complex shapes and objects will be (more polygons are displayed), but the lower your performance. I recommend Medium or above for a good balance of performance and realism, unless you have 256MB of RAM or less, in which case set to Low.
Effects Quality - Has Low, Medium and High settings, with the higher the setting the more effects displayed, but the lower your performance. Again, Medium or higher is recommended unless you have 256MB of RAM or less, in which case set to Low.
Environment Mapping - When enabled, shows environmental effects on weapons and vehicles. However there is virtually no difference with it enabled or disabled, so disable it if you need more fps.
Lightmaps - When enabled, shows more detailed shadows on and within buildings and structures. Again, there is minimal noticeable graphics quality decrease with this option disabled, so disable it if you need more fps.
Shadows - When enabled shows complex dynamic (moving) shadows for soldiers and vehicles. You won't see these shadows if you disable this option, however fixed objects (like trees and buildings) will still cast their shadows, and you'll get a performance improvement without any noticeable drop in graphics quality.
Texture Quality - The higher the percentage, the crisper and more detailed the textures will look. However the higher the texture quality, the longer the load times and the more texture memory will be used to load these detailed textures. If you have a 32MB graphics card and 256MB of RAM I highly recommend lowering the texture quality to around 50% or less to noticeably improve performance, particularly if there's any 'stuttering' problems (see Troubleshooting section).
View Distance - The higher the percentage, the more of your surroundings you can see, but the lower your performance for it. This setting affects gameplay a great deal, because if an opposing player has a higher view distance than you, they'll see you first and thus have the advantage. I recommend leaving this at or near the 100% mark. Lower other settings first to gain fps before lowering this.
Alternative Spawn Interface - This changes the spawn point selection interface whenever you bring it up. Selecting this option will disable the background scenery while you choose your spawn point. It can improve performance slightly, especially if you have a laggy mouse during spawn point selection, so I recommend selecting it if you need the boost.
Don't forget to hit the Save button before exiting this screen.