You can find the user defined settings in the following directory:
C:\Users\<Username>\Saved Games\Littlewitch\Romanesque ep\UserData
Display settings are saved in Config.ini and you can edit them with Notepad or any other text editor. The default settings are below:
Config.ini
// System Config
PosX = 1040
PosY = 93
Width = 800
Height = 600
IsSyncReflesh = false
IsCancelScreenSave = true
IsCancelSleep = true
IsCancelMonitorOff = true
IsDiagnosis = true
IsAutoPause = true
IsAutoMute = false
BaseFPS = 60
IsValidExitDialog = true
IsUseMMX = true
IsUseSSE = true
IsReadyable = true
IsSyncable = true
IsHideCursor = false
IsLockWindowSize = true
// Graphic Config
IsAntiText = true
IsPlayMovie = true
IsSmoothScreen = true
// Sound Config
IsUseSound = true
IsNoiseCut = true
IsPlaySE = true
IsPlayVoice = true
IsPlaySystem = true
IsPlayBGM = true
SEVolume = 90
VoiceVolume = 60
SystemVolume = 90
BGMVolume = 90
// Screen Config
ScreenMode = 1
FullMode = 0