But don't worry. There will be a fairly good alignment of the planets Mercury - Saturn in May of 2000. But there will be no ill effects from this alignment. The planets are much too far away. The combined gravitational effects on the earth of all the other planets together is only about one five hundred thousandth the force of the moon.
Planets are typically brighter than most stars.
Planets, however, usually do not twinkle. So if you see a bright, star-like object that's not twinkling while other stars are, it's probably a planet. Finally, color is often a clue for some planets. Mars is reddish-orange and Saturn is yellow. I'm not aware of a particular name for this.