You cannot disable the Screen Saver but you can change its start time; however 5 Hours is the longest Start Time:
Contour button > Settings (gear icon) > Device Settings > Screen Saver > Screen Saver Starts After:
The Screen Saver only starts if your TV is not fully displaying a channel. For example, if Contour is tuned to Nickelodeon, your TV must be fully displaying Nickelodeon. You cannot have any Contour menu displaying on your screen. For example, the Program Guide cannot be displayed on your screen, information about the program (Info) cannot be displayed on your screen, etc. To disable the Screen Saver, do not open any Contour menu while awaiting for whatever you're waiting.