October 31st is the Feast Day of all the Dead. Someday it will be our feast day. It is important to treat the spirits as you wish, someday, to be treated. Welcome them. Cautiously. Also, buy the good candy. Spirits get extremely angry if you give them raisins.
In many cultures, it is believed that on this day, the dead return to walk among us. Obviously, this is foolishness. The dead walk among us always, we simply prefer not to acknowledge that fact. However you celebrate this particular holiday, with feasting and memory, with costuming and mummery, or by locking the doors and praying, may your day be a peaceful and rewarding one.