[Phantasm]

As this is DF, and the Dungeon Fantasy genre is based in large part off Tolkien's writings, I believe we can make a few assumptions:

Humans live 70 years on average before complications of old age catch up to them. Dwarves live about ten times that, while Elves tend to live indefinitely - or over a millennium if you want really old Elves rather than timeless Elves. Halflings average about 100 years. Orcs and Goblins are the "live fast, fight hard, die young, leave dirty underwear" types, so I can see them having shorter life spans, averaging 30 to 40 years, though "civilized" Orcs may live as long as their Human cousins. (If using Warcraft tropes, Goblins may also have a tendency to blow themselves up, leading to a shorter average life span.) YMMV, of course.

Other races, I'm not quite sure of honestly.