You can't go wrong with white on walls in a kitchen, but the color is more than just a failsafe. White will pull together disparate elements of a kitchen like modern steel appliances and a vintage sink and counter or granite countertops and beadboard walls. Paint ceilings, trim, cabinets and walls stark white or creamy vanilla, keep the look uncluttered and add a pop of color with a glazed ceramic cookie jar, some bright dishtowels or painted wooden chairs.
Walls painted in matte terra cotta can handle painted tile backsplashes, big fruit bowls, wood cabinets and touches of Tuscan color everywhere. Grow some green plants in this kitchen, and select a stone or wood floor to balance the intense walls. Painted chairs or stools around an island or kitchen table would work well. The room will need lots of good lighting at night and on overcast days to keep it sunny and cheerful, like the warm Italian region that inspires it.
Robin's egg blue or soft turquoise on kitchen walls is restful, whether the look is vintage or contemporary. In a period kitchen, a muted turquoise will harmonize with older appliances, linoleum tile floors and Formica countertops. A modern kitchen of brushed steel appliances, stained wood cabinets and slate countertops can handle a strong robin's egg shade as well as the punctuation of a vivid orange pendant lamp and an orange cappuccino maker or enameled mixer.
Yellow is a classic kitchen color for good reason. It's cheerful, bright, goes with nearly everything and can transition from country to urban kitchen without missing a step. Try warm mustard yellow on walls, and frame it with shiny white trim. Or go for palest butter cream, and define the walls with the complementary color, blue-violet, for the trim. Big, colorful vintage posters framed on the walls -- citrus advertising or circus billboards -- could be fun with either shade.