elves

Elves are similar to the Fae in many ways, for they too have there own type of magic, many of the races are of similar shape and appearance, and there are many races of both species.
They are many different thing; musing and poetical, wise, solitary, agile. There are too many races to generalise too much; the description above does not fit for all Elves. For example; house elves are found all over Wizarding society; their purpose in life is to serve and help their master, and their loyalty is unwavering. High Elves, however, are proud and noble people, living away from other non-elfin communities.
Their appearance also varies through the races. High elves are tall with golden skin and hair, and bright blue eyes. They are completely different to the stereotype of an elf, looking almost human, though destinguishable through their delicate features and grace. Wood elves are different again, with long dark hair and pale skin, with green patterns in their skin. House elves are short and strange looking, they have huge eyes and long, leathery ears.
I could not possibly try to generalise the characteristics of an elf, for they vary too widely. However, elves in general are known for their quiet, isolated lives. They study and preserve life, and have strong bonds to the Earth.
A relative of elves are the Dryads, who have a bond with trees. When a dryad is born they are given a tree which they invest their lives in. If they die, their tree dies too, and it works the other way around. I mention this to illustrate the bond between the earth and elves.
The elf races vary due to the different habitats. Dark Elves, also known as Drow, live under the earths surface. Their skin is dusty black, their hair is silver and their eyes are red. They are often disrespectful to humans and to their elven kin, and they have consequencially developed a bad reputation.
Death
Nobody knows much about the deaths of elves - or indeed whether they do at all. I do know that in most races their aging is far slower, and they never lose their radiance.
Elves have certain way about them, a brightness and radiance about them that they never lose, and defines them as elves. This they never lose.
Health and Characteristics
Elves do not get sick. They have a higher threshold to pain, and a greater constitution. They are stronger and more agile than the average human, they have more stamina and generally more energy.
Elves are incredibly curious beings. They study the earth and help it, as well as all they life on it. They are full of love and vitality, and give all they have to help nature.
Elven Magic
Elves have their own special magic which also varies between the races. It can be immensly powerful in its own way, depending on the user and the intent. It is complex magic which can be learnt by human wizards, but it requires the same frame of mind that an elf has, so a human learning elf magic is rare. However, when a human learns to use elf magic it is the first step to understanding the way of an elf.

Recommended reading

I highly recommend that if you are interested in elves you check out the Elven Way by Ilon Bluesky (I have no idea who he/she is, just something I came across) from Elven Glen (and I can't find anything on that either :o( ) which you can access here.

www.jps.net/elve/silverelves.html
www.geocities.com/area51/station/1774/elves.html