Orcs: You may be thinking orcs are very big, mean, brutal, strong, and stuff. Well, they pretty much are, but before the portal opened to Earth (or wutever dat planet is), they were as peaceful and noble as Humans were.

Night elf: Now Night Elves were awakened way before the humans were born. They had a life with magic, always studying them, and testing and looking for new magic. Unfortunately, this whole magic 'festival' drew the burning legion to the 'Earth planet', because burning legion need to absorb the magical energies of planets, with the NE fighting the BL. ( The NE were NEVER, EVER, EVER mentioned in the Wc 1 stuff) Eventually the NE's won, and the burning legion came back in Warcraft 3: reign of Chaos, attempting to try again.