is it possible to be a drow or anyother of those kinds of races?

Nope. Only Humans, Half elves, Elves, Halflings, Dwarfs, Gnomes and Half Orcs.
sorry.

some guy said that he made a half-drow, what is all that about?

if you do, let's say, make a drow can you give them special abilities? or anything like that?

[This message has been edited by Ladonna (edited August 11, 2001).]

ShadowKeeper is probably the culprit. You can get it here: http://www.sorcerers.net/Games/BG2/index_editors2.htm

It can be used for good and for bad, so use it wisely.