I'm a Slytherin

My parents were upset when I told them this. I can't see why, Slytherin is just as good a house as the rest, thank you.
Which brings me to Hogwarts houses! I have a bunch of questions, so answer them if you can. PLEASE.

• What house was Dolores Umbridge in?
• Why, exactly was Peter Pettigrew in Gryffindor? Enlighten me.
• Was Remus John Lupin most certainly in Gryffindor? It's never mentioned.
• Why has Ravenclaw never been shown playing a Quidditch match in any of the books or movies?
• That's it, actually.

In other news, 26 days to the DH premiere! Yes!
SMELLY SOCKS
"You know your mother, Malfoy? The expression on her face - like she's got dung under her nose? Is she like that all the time or just because you were with her?"
--
Harry Potter