The 4:3 option only appears in the list of available picture formats if you connect a computer by VGA or HDMI.
If you want to view TV channels or material from other Sources in the 4:3 format, you need to set the picture format to [Auto Format] and select [Auto Zoom] in the [Auto Format Mode] Menu.
Follow these steps to set the [Auto Format Mode]:
Press the [Home] button on the remote control to access the [Home] menu
Use the cursor button to select [Setup] and press the cursor [OK] button to confirm
Press the cursor [Down] to select [Picture] and press the cursor [Right]
Press the cursor [Down] to select [Picture Format] and press the cursor [Right]
Select [Auto Format] and press the [OK] button to confirm
Press the cursor [Down] to select [Auto Format Mode] and press the cursor [Right]
Select the option according to your preference and press the [OK] button to confirm
When AUTO FILL is selected, the picture will expand to fill the screen regardless of the broadcast format, e.g. 4:3 or 14:9
When AUTO ZOOM is selected, the picture will be displayed according to the broadcast format, i.e. TV will display 4:3 broadcast in 4:3 format; 14:9 broadcast in 14:9 format
Press the [Back] button to exit the menu