Generally it's best to mobilise the joints to warm up: so alternate knee lifts, swinging one leg back & forth then the other for hip mobility, kicking alternate heels back to bottom, jogging on the spot etc all do the trick.
Don't bother with pre-run stretching - it reduces muscle power and wastes time. Just start out slow jogging for the first mile to warm up and gradually pick up the pace.
Always do a cool down, don't just stop or you can feel ill. Walk around for a bit, maybe 5 mins, then when you're home stretch calves, hams, quads, hip flexors and lower back. Then I do the sitting quietly with a nice cuppa ;o)