Can you tell us about your kitchen cabinets other than sad? What are they made of... wood, pressed product, painted, greasy, broken...? Lots of options. Do you have a picture of them you can post?
The most important thing to do is clean them well before you paint. Here's a link for you:
Take a good photo (or better yet a cabinet door) to the paint dept. at your home improvement store and ask for their professional advice on materials and application methods.