Oh dear, a book load of questions (and a life-time of learning...)(posted 9879 days ago)There's no such thing as "best". I use Kodak and Ilford; others use Fuji and Agfa. Whatever your friend;y photo-shop sells.
Don't start messing around with filters before you've got some experience behind you. But the brief answer is: the human eye does not have an equal response to all wavelengths: it is more sensitive to yellow-green. A filter of a given "colour" lets through more light of that colour. So a yellow-green filter will make the B&W film "see" colours in tones that more closely match the human eye.
Kodak have a new chromogenic film, like XP2, called, umm, TCN400 I think.