If you are tired of your old wood, plastic or even metal faced cabinets its ok to spruce them up with a fancy new paint job, the most important part is to prepare the surfaces first.
1. Remove the doors and all hardware (knobs, hinges and so on)
2. Scrub all the surfaces you plan on painting with a T.S.P solution and then roughen up the surfaces with some 220 Grit sandpaper and wipe down all the dust.
3. apply a good quality shallac or enamel undercoat primer (tinted near your end color).
4. Grab your brushes and roller and apply a nice enamel paint.
5. carefully install the doors again and put the knobs back on.