3 unrelated OOP questions

[leb2323]

No: HPFGUIDX 96531

I just finished yet another re-read of the entire series and ended up
with a few new questions from OOP.  Of course I want to start out 
with the standard "if this has been addressed already then I
apologize" disclaimer.  With that said, here goes:

1.  Does the Knight Bus get from place to place partially by
apparating?  When wizards apparate they make a popping or cracking 
noise that I assume correlates with the level of competence or
experience they have.  The Knight Bus jumps from place to
place with a loud "bang".  Ch 24 (Occlumency) of OOP describes this: 
"From here they moved  to a main street in the middle of a busy town,
then to a viaduct surrounded by tall hills, then to a windswept road
between high-rise flats, each time with a loud BANG."  

2.  In ch 17 when Harry takes the injured Hedwig to the staffroom to
find Professor Grubbly-Plank one of the gargoyles calls him 
"sunny Jim".  Is this just some type of british phrase that I'm
unaware of or is it an allusion to his father James and the fact that
they look so much alike?

3.  When Dobby has warned the DA that Umbridge is on her way and the
members are all scattering while Dobby is "punishing" 
himself for warning them, Harry grabs him up and says, "Dobby -- this
is an order -- get back down to the kitchen with the other elves, 
and if she asks you whether you warned me, lie and say no!" said
Harry.  "And I forbid you to hurt yourself!" he added, dropping the
elf as he made it over the threshold at last and slamming the door
behind him.  "Thank you Harry Potter!" squeaked Dobby, and he 
streaked off. (ch 27).  Now, I am of the opinion that Dobby at one
time was the Potter house elf before he was relocated to the Malfoys 
after James & Lily died.  Am I way off base and trying to read too
much into this scene or is Dobby taking a direct order from Harry as 
if Harry were Dobby's master?  I've read this book countless times
now and this bit just really jumped out at me this time.  

I'm looking forward to reading everyone's opinions/answers to these
questions!

leb