It's pretty important to use a primer coat, particularly if they have not been painted before. It will seal the wood, and allow your new paint to cover well. Otherwise, it may take many, many coats of paint to get the coverage you want. It's also important to sand them before you put on your primer coat. You don't have to do a lot, just go over them once, enough to slighly roughen the surface, with maybe about a 150-200 grit.After you've primed and sealed the surface, get a paint that is designated for kitchen and bath. It should have a hard, gloss surface, one that can be cleaned easily and will repel rather than absorb. Any home improvement store such as Lowes or Home Depot carry them, and they can be tinted to any color you like, even custom colors offered by other paint brands.