The most commonly used options.txt configurations are:

Additional parameters:

• Brightness [0.0 to 1.0]
• MultiSample [0 for none, 1..N otherwise]
• AdvancedPhysics
• PathEditorCameraFollow
• PathEditorGUIMode
• TrackEditBackwardsLikeRCT2
• Firsttime
• SkipCacheWarming [<float> in seconds]
• TrackEditorMovesCamera
• ShowTrackSectionSymbolNames
• AllowTestAllTrackedRides
• PauseOnLoseFocus
• TrackAllowSameTrackIntersect
• AttractionSceneryAllowSceneryIntersect
• AttractionSceneryAllowTerrainIntersect
• DynamicBatchTriCutoff
• StaticBatchTriCutoff [<tricount>]
• DetailMapTerrain
• AutoScrollAtEdge
• LevelTerrainUnderTracks
• SmoothDuringAutoLevel
• AutoLevelTerrain
• Swaying3dTrees
• HighQualityTrees
• ImportMyMusic
• RidesDontBreakDown
• GuestsHaveNoCamcorders
• GuestsHaveNoCameras
• GuestsRideUnratedRides
• GuestsRevisitRides
• GuestsIgnoreRideCost
• GuestsIgnoreNausea
• GuestsIgnoreRideIntensity
• GuestsHaveFixedHealth
• GeometryImposterTolerance
• SceneryVisibilityAlpha
• Bloom
• ModulateX2
• Shadows
• CameraUserControlMode [<0, 1, 2, 3?>]
• CameraIsometricContols
• CameraIsometricView
• CameraFocusIsMiddleScreen
• DistantMountains
• ReflectBackground
• MaxTerrainTypes
• DisableHorizonMapping
• DisableAutoAnimalInjection
• SkipBannerSequence
• SkipStartScreen
• RideLOD [LOD (?)]
• TrackLOD [LOD (?)]
• SupportLOD [LOD (?)]
• BuildingLOD [LOD (?)]
• FenceLOD [LOD (?)]
• MaxMusic [Maximum simultaneous music]
• MaxSounds [Maximum number of sounds]
• MusicVolume [Music volume (000-100)]
• GUIVolume [GUI volume (000-100)]
• GameVolume [Game volume (000-100)]
• TemperatureUnits [0 for Celcius, 1 for Fahrenheit]
• Units [0 for metric, 1 for imperial, 2 for SI]
• Currency [0-9 for £, $, €, ¥, Kr, NT$, AU$, NZ$, HK$ or SG$]
• ScreenGFDriver [0 for GF2, 1 for GF4]
• ScreenPixelFormat [0 for A8R8G8B8,1 for R5G6B5,2 for X8R8G8B8]
• Fullscreen
• Resolution [<x> <y>]

Soaked! Expansion:

• [<keyId> <keySequence>] Keys
• [language?] Language
• [“Title of background music file”?] BackgroundMusic
• ShowPersonStateToConsoleButton
• Bool_AutoDetectBatchCutoff
• WaterDroplets
• DebugAids
• EnablePointerLight
• ShowSkirtTrees
• MovieCaptureAVI
• TrackForceCanStart
• PoolEditorDrawGrid
• PoolPathEditorGuiMode
• PathEditorCameraFollow
• PathEditorGuiMode
• TakeVistaPointPhotos
• TakeCoasterPhotos
• TakeAllPhotos
• AggressiveZBias
• EnableIME
• LaserRayHit
• Refraction
• Bloom
• ModulateX2
• InvertRideCamYAxis
• BlendSceneryLODs
• CompressTextures
• CameraIgnoresScenery
• WaterFlowEnvMap
• Sky
• Clouds
• CorrectDayNightCycle
• GrowGrass
• ReflectParticles
• ReflectPeople
• ReflectScenery
• ReflectTerrain
• ReflectInMultipleSurfaces
• WaterBumpEnable ReflectEnable
• DisableWeather
• DisableAutoPersonInjection
• SkipBannerSequence
• TrackedRideUpdateFreq [+ve for fixed fps, -ve for capped fps (?)]
• GeometryImposterTolerance [<Tolerance>]
• GeometryImposterDistance [<Distance>]
• SceneryVisibilityAlpha [<Alpha>]
• SceneryLOD [<LOD> (?)]
• PathLOD [<LOD> (?)]
• VegetationLOD [<LOD> (?)]
• AnimalLOD [<LOD> (?)]
• GuestLOD [<LOD> <ViewDistance> (?)] (?)]
• GraphicsQuality [0-4 or 5 for Custom]
• AlphaRemap
• AutoLODDensityEnd
• Density AutoLODDensity
• ShadowsType
• ShadowsDetails
• Shadows
• CameraControls [0/1/2]