How can I successfully ask out a girl who shares no common interests?

I'm a lil bit older than 21. I have a weird crush on a senior still in high school. Girls I've been in serious relationships with actually shared some interests with me, but I want to be able to successfully ask out a girl who holds absolutely no common interests. I'm tired of being with girls with similar personalities as mine. I want a total extrovert/wacko. She smiles at me a lot at the office, but I have no idea what that means, because the smiles aren't half-assed like when she's posing for a picture. And I'm only staying at the office for a short while so I don't mind the "don't dip your pen in company ink" motto. But I don't want to be fired, so I only talk to her during short 3-5 minute breaks. And finally, she's the most beautiful girl I've met, in my eyes, so I feel like this is a must for me. So how should I go about asking her out?

How's being around 21 pushing 30???

leave it alone. the girl is still in high school and you pushing 30! her smiling doesn't mean she likes you, she is just smiling. you guys are co workers so she is just being nice. try dating chicks on your level. you're probably the type that circles high schools lookin for an impressionable girl that you can corrupt, you need to stop!