Cardigan, dress shirt, and what type of tie

I have a gray cardigan, a red dress shirt and a blue dress shirt, and a black bowtie and necktie. The question is what do I wear to college. The cardigan is a must because the dress shirts themselves are too big (only ones that would go well with shoes, pants and overall outfit) and the cardigan, being a small, makes it look fitted and like the dress shirt is my size instead of one size larger. So the question is what would look better, a bowtie or necktie, and the cardigan buttoned up or down?

Also, the shoes I wear are NOT dress shoes, I skate around campus and I can’t really skate in dress shoes. I also don’t have eyewear or contacts either, and my hair is black.

2 Button Dress Shirt Collar? Good, Bad, Ugly?

I’m purchasing a number of made to fit dress shirts and saw an option to have 2 buttons instead of 1 neck button on a wide spread shirt. While I’ve read Alan Flusser’s Style & The Man, I haven’t seen anything referencing this.

How would this affect the presentation of the shirt? Would it make it more formal, casual, over the top, lacking style etc?

Here are 3 pictures that illustrate it:

http://4.bp.blogspot.com/_7gmscB9QAcc/SmHtRJRcIeI/AAAAAAAAAEE/Wum3mD1H81U/s320/MS-HU7005m.jpg

http://www.debonairmag.com/wp-content/uploads/2009/09/Collar-Double.jpg

http://manolomen.com/images/Putins%20collar.jpg