Although I can't be certain, I'm 99% sure it's a Goblin.
I'm 100% sure it's a Dunmer.
It doesn't look like any of the goblins that we've seen in any other Elder Scrolls game.
- http://images.uesp.net//b/bc/OBCreature-goblin.jpg
- http://images.uesp.net//1/1d/TR-creature-Goblin.jpg
- http://images.uesp.net//a/a0/ArenaGoblin.gif
If it was a goblin, it's neck would be jutting forward rather than up. I would also say that it's too slender to be an Orc.
It is definitely a Dark Elf, it doesn't look like anything else to me.