Changing the colour scheme to high contrast colours can help improve legibility and make it easier to use the menus. You can change this in the settings menu.
Bring up the menu on your remote
Select Settings*
Scroll down to the Accessibility & Language area and select Appearance
Select High contrast colours
Change this to On
Select Done
*Settings can be found via the cog in the top right corner of the Menu. You can get to the cog by pressing Up and right after opening the Menu.