That Krylon Fusion paint works GREAT for what you're looking to do.
One thing - make sure you clean the plastic off really well before painting, that's what usually helps it to flake off, painting over crap so it doesn't adhere real well.
When painting plastic, I always went and bought a bottle of cheap alcohol (from the drug store, not the liquor store

) and some paper towels, and wipe down everything VERY well with it. You bought the whole bottle, might as well use the whole thing! Obviously concentrate on the areas that will be seen, and not nearly as much as the rest.
Let it dry. Paint away. Like Peale said, cheap paint works just fine, but since Krylon came out with the stuff, I've used it, and it just seems "tougher"....I'm not as afraid to scratch it, and it seems like it doesn't sit on top of the plastic like regular stuff does.