1. Do NPC classes grant the character a favoured class bonus - for example would a ratfolk expert be able to take expert as his/her favoured class and either add one skill rank or one hit point?
2. Do NPC classes give the right to take full hit points for the first hit dice or is that just player classes?
1) Depends on if you want them to. In general, even most combative enemies don't have favored class bonuses. If you want them to, feel free. There are no guidelines on who should and shouldn't have them.
2) Another subjective thing. In general, most NPCs do not get full hit points at first level. It really depends on what you want in your world. I believe most stat blocks have them at average HP.
2)is easy, answer is right at the beginning of the book. A creature gains maximum hit points if its first Hit Die roll is for a character class level. Creatures whose first Hit Die comes from an NPC class or from his race roll their first Hit Die normally. (scroll down to hit points)
1)FCB doesn't limit itself to character classes and doesn't exclude NPC classes, so I can see no reason not to.
Each character begins play with a single favored class of his choosing—typically, this is the same class as the one he chooses at 1st level. Whenever a character gains a level in his favored class, he receives either + 1 hit point or + 1 skill rank. The choice of favored class cannot be changed once the character is created, and the choice of gaining a hit point or a skill rank each time a character gains a level (including his first level) cannot be changed once made for a particular level. Prestige classes (see Prestige Classes) can never be a favored class.
that's very helpful, thank you