Definitely Half-Elf.
I'm 5'9 and 135 lbs, which is well within the range of Half-Elf (and almost dead-on the middle of the range in the 2nd Edition charts). I'm of very thin build, something of a social outcast, I've got exceptional night vision and my hearing and vision are above human average. I look significantly younger than I am (I'm 26, people tell me I look 19 or 20), and my family is known for being very long-lived. I have a deep love of nature, I eat little meat and prefer vegetables, and after some hostile run-ins with very crude and barbaric people in childhood, you could say I'm not very friendly with Orcs and Half-Orcs.
Not so much for D&D elves, but I am also significantly allergic to iron and my skin blisters and burns at the touch of the metal, which isn't goibng traditional D&D elves, but does fit with elves from other sources.
As for class? I'd say Smart Hero 3/Dedicated Hero 2 (as d20 Modern is most appropraite), going towards Martial Artist and maybe Occultist AdC's.