Hey,
I'm new to biking and was looking to get a fixed gear bike and came across this http://www.bikesdirect.com/products/windsor/thehour.htm the Windsor The Hour. I was wondering what size I should get if I'm 5"1.5 and 95lbs?

Also if I wanted to switch out to a 17t cog which one should I get? And would switching out the cog mean I would have to get a new chain? Also what are some good colored tires and a bottom bracket?

Sorry for asking so many questions...

Thanks, Alex