In regards to the font size, I think it's fine for Arial. If it were that font size with font style Times Roman, then it would be too small.
Here are the grammatical problems with your resume:
"Possess extensive knowledge in computer usage. Self taught experience in building computer systems and hardware/software troubleshooting, including hardware installation and optimization.
Proficient in Korean"
First off, "self taught" should have been hyphenated. It should be "self-taught". Secondly, just when you think that no one's observing what seems like little things, someone out there also known as your potential employer is observing things you do.
Your resume reveals someone who isn't sure of himself. Here's why: On your objective, you fail to use a period to end your sentence. And then on other subcategories, you use periods on some spots but don't use it on other spots. You must be consistent. There should be a period at the end of each sentence. It should be "Proficient in Korean." Your mixture of periods and no periods doesn't seem like a deliberate thing and style. It looks like it's done unintentionally.
But don't go putting periods in the IT Support Lab Assistant category. That one is fine as it is.
Your objective doesn't look right in spacing. I don't know whether you used a tab or something somewhere there, but it looks overly spaced. Keep it consistent with your other spacing in other subcategories.
Lastly, it's okay to write the following as you have it: "Responsible for proper closing, organizing inventory"[/i] However, it isn't smooth when reading it. Why not write, "Responsible for proper closing and organizing inventory"? I hope that helps.
Well, one more thing: "Major in Business Marketing, minor concentration in Graphic Design; Class of 2004 GPA 3.1"
How about a semi-colon in between the major and minor? Then a period and Class of 2004; GPA 3.1?