The Screen menu in Super Smash Bros. Brawl gives an in-game means of changing the widescreen settings of the Wii console to match the television being used. It is accessed via the Options menu from the main menu. By default, it inherits the setting enabled in the main Wii console options, though players can choose to override this setting.
The two options are:
A circle appears in the background on this menu to help the player see which screen size is more suited to their TV.
Changing the screen ratio does not change the Wii's output resolution, which remains at 640×480, even on the default PAL setting of 576i 50Hz; only the way the picture is rendered within that resolution is changed. As a result, snapshots captured on a widescreen-set console will appear in a 4:3 aspect ratio if decrypted and viewed on a PC.
A method to switch between 4:3 and 16:9 ratios did not return in the Wii U version of Smash 4, and instead, the selection between 4:3 and 16:9 is done by modifying the settings of the Wii U. Regardless, Smash 4 itself does not support 4:3 ratio; if the Wii U is set to output at 4:3, the game will be letterboxed as to keep it at a 16:9 ratio.