i agree with manboy on the frame size, i'd rather have somthing a bit smaller than a bit to big, mostly for handling and response,
as for the parts, NYC bikes has been making some really nice high flange track hubs, their not incredibly expensive and only come in pairs, but their pretty much bomb proof,
any of the campy track hubs wont' let you down, you can find those on ebay not to expensive, suze makes decent flip/flop hubs as well,
BB, can be as good as you want to put down for, i would go sealed,
as for cranks, you can't go wrong with any of the sugino, campy track sets, the shimano dura-ace track group is nice as well,
to be honest, you can't go wrong with track components on a fixey
choosing the parts for one is a really personal thing,
i would try to find the parts at your LBS and take a look at them, you might not like the look or feel once you do
so
choose wisely