This doesn't belong on the wiki but who cares it's the Games Tent board and it's useful info anyway.
1. Are the books and movies in the same universe?
Yes. They just take place in different times (in a way). The movies take place in the past, which is hinted heavily by the use of old technology and other stuff like that. Everyone gets confused because almost none of the fairies from the books appear in the movies, although they have stronger characters and were more important in the story at one point. I can see why Disney didn't want to include them though, and went with simpler and more comedic characters. But we'll get to that later in #2. So, one of the biggest things that confuses people is that in the books, the Home Tree exists instead of the Pixie Dust Tree. Well, according to In the Realm of the Never Fairies: The Secret World of Pixie Hollow (2006) and Tink, North of Never Land (2005? 6? Who knows, honestly?), the Pixie Dust Tree was destroyed a long time ago by an evil force that no one dares mention for fear of summoning it, and was replaced by the Home Tree after a hurricane (I think. It's extremely unclear right now.). The fairies from the books are technically in the movies, but I'll explain that later. Some holes in this include the fact that in Tink, North of Never Land, TinkerBell talks about pixie dust as if she has never seen or used it before, and in the same book, she gets mad at Terence because he accidentally destroyed her silver bowl, which was the first thing she repaired after her arrival. Because of this, it is unclear if the Tink we see in the books is the same as the one in the movies, if that makes any sense.
2. Why don't any of the fairies from the books (Rani, Beck, Bess, Prilla, etc.) appear in the movies? (companion to previous)
They actually do, all except for Prilla (see above) because she was not born yet. No one is sure if they appear as background fairies (too many of them!) but if you have any of the DVDs, some of them have more bonus features than others. If you go to some of them, then the fairies who star in the book make appearances longer than a few seconds! You can tell it's in the same time period as the rest of the DVD because Rani appears with her wings! So, there's proof already. Something else that links the books and movies is that in one of the bonus features, they explain the ancient writing system of the fairies, Leaf Lettering, which was really only fully explained otherwise in 'In the Realm of the Never Fairies'.
3. Oh, so, Clank and Bobble can go into the Winter Woods with Tink in the first movie, and now all of a sudden it's forbidden?
Ok, I agree it was a little strange how they were all so terrified of the Winter Woods all of a sudden when they flew through like it was nothing in movie 1, but still, this question can be answered. They were only in there for a few seconds. As you can see in Secret of the Wings, a few seconds doesn't do much harm other than make you cold. So stop asking this. It was always forbidden.
4. Who's older, Tink or Peri?
TinkerBell, by one second. This is clear in the movie from subtle differences in their hair, but also in the magazine comics, where the hair is colored in. A reason for this could be the delayed travel of pixie dust from the tree to the woods.
More coming soon.