A human, from the ubiquitous 'northern' area of any setting where the big, burly, fair-skinned guys come from.
You see, I'm about 6'6" tall (198cm for you people who use a sensical measurement system), and around 300 pounds (~137kg), and I have especially big shoulders muscles and long legs. I'm quite strong for someone who doesn't work out regularly (about a 14 or 15 if you go by carrying capacity), and I've got a bardlike array of knowledge (I call it my 'nerdic knowledge' ability) which I can apply effectively to all situations outside of sports, music, and women/girls, which (it turns out) also doubles as a good way to impress girls. I've also got long, fiery-red hair and a fairly well-kept beard, which makes me look like a viking when I don't have the hair back and I'm in my rough outdoor clothes.
I tend to prefer swords and spears, but also have a special place in my heart for long-hafted impact weapons. My favorite colors are blue, green, black, and silver. I hate city life (though I don't mind visiting), and I hate warm weather and sun even more (since, like a cat, I become sleepy and ill-tempered in the warm weather, and as a red-head, I get a 'pink' instead of a tan when I'm out in the sun). Along with gaming and related things (writing, history, science, etc.), I have a particular passion (and at least a minor talent) for making things out of metal and wood, and cooking meat on the grill or in a pan.
I'm definately not a dwarf (too tall; beard is too short; too intellectual; too neutral on the law/chaos axis)
I'm definately not an elf (too big and hairy; I enjoy large, strong-flavored meals too much; while surprisingly fast and non-clumsy for my size, I lack any sort of grace, and I have a very high tolerance for pain, oh, and I'm a stubborn bastard.)
I'm anything but a halfling (too big and tall, too strong, too graceless, too sensible and calm)
It would be funny to even suggest that I'm a gnome (too big and tall, sense of humor is all wrong, and much much more)
If anyone suggests I'm a half-orc, they're wrong (too intellectual, not strong enough, too hairy (!), too much preference for peaceful solutions)
Half-elf is just as wrong as elf (for the same reasons, plus the fact that I'm well-adjusted and (outwardly) self-assured)
I'm a human. End of story.