The term "magical" does not refer to a singular race. Rather, "magical" is a classification of race, like "Non-Magical" or "Monster".
Magical races are the races that were trapped in the Magical Realm when the world was sundered.
All magical creatures have the ability to subsit entirely off sources of magic. Not only do they produce their own over time, but in areas with large amounts of magic (such as the Magical Realm), magical creatures don't need to eat and they heal an a rapid rate.
Magical creatures have either incredibly long lives, or are actually simply immortal. Without some sort of outside interference, magic will constently repair any minor injury and stop the effects of aging.
It still is possible for immortals to die; they have to be killed either intentionally or by gevious injuries that kill them faster than magic can repair them. It's almost unheard of, but technically possible.
The older races have members who were around at the creation of the world and personally lived through historical events. This means that they have a much more accurate picture of history than Non-Magical races, or even Monsters.
See the History of the Magical Realm.
Magical races are limited to the Magical Realm, and will find themselves weakened in the [Living Realm][].
Due to the residual magic generated by Monsters in the [Living Realm][], it is much more hospitible for magical creatures than it used to be millenia ago. Recently more powerful magical creatures have found they can survive for days or weeks in the [Living Realm][], especially if there's a colony of Monsters nearby.