The script for Chamber of Secrets describes the scene thusly:
Harry starts to set the diary aside, then notices a
BOTTLE OF INK sitting on the desk. An idea flickers.
Taking his QUILL, Harry dips it, and hesitates. As he
does, a DROP of INK hangs, suspended like a tear, then...
The ink BLAZES briefly, then... VANISHES... as if ...
Riddle is not fully formed yet. He's a memory almost made flesh, so he can grab Harry's wand and even create some shiny letters with it, but it's possible that's the extent of his powers.
Riddle also knows that the Killing Curse didn't work on Harry once and rebounded on Voldemort, so he might be wary of trying this powerful spell again ...
He's saying that the school will be missing something for him if Hagrid is gone, that the experience is lesser without Hagrid. That it just doesn't feel like the same place without Hagrid there. But why?
Hagrid is a very important character to Harry. For several reasons:
He told Harry that he was a wizard
He was a friend of Harry's parents
He's helped out ...
JK Rowling has actually addressed this very subject, at Carnegie Hall in 2007:
Question: When Harry was stabbed by a basilisk in the Chamber of Secrets,
since he was a Horcrux shouldn’t it have been destroyed then?
JK Rowling: I have been asked that a lot. Harry was exceptionally fortunate
in that he had Fawkes. So before he could be destroyed ...
OK, since that other SE question seems to suggest that Rowling never supplied a canonical answer, we'd just have to settle for a plausible explanation: It's a magical snake and a magical school.
After all, in the Harry Potter universe, things are impossibly squeezed into smaller things all the time. Remember, for example:
That people enter the Ministry of ...
There's a choice of possibilities... According to Dumbledore, the Ministry of Magic can detect when magic has been done near an underage wizard, but not who actually performed it. So on a train full of underage wizards it's perhaps just too difficult to enforce the rule.
More likely, the Hogwarts Express is deemed an extension of school property, so it's ...
It's just a figure of speech
Harry and Hagrid are friends, if you were at school and your best friend/favorite teacher didn't go that day. The school wouldn't be the same for you.
It just means that Hogwarts for Harry (and for anyone that likes Hagrid) won't be the same.
With Hagrid in Hogwarts, Harry has someone besides Hermione/Ron to talk to. We can ...
The spell (used in the movie) was used in the presence of spiders. It's really that simple, I think. I used a Search function on my PDF of the book and it produced "No results." It seems to be an invention of the film and one only used in the presence of spiders.
Why would Harry use it when there were no spiders around?
Tom Riddle was draining her life force (for lack of better term) so while Ginny was getting weaker, he was getting stronger. He needed her in his plan so Basilisk shouldn't kill her on his orders. He also didn't kill her with its gaze, because Ginny had her eyes closed (being in coma and all).
Throughout the book, we see that phoenixes have various abilities. One of these appears to be the ability to Apparate (or something very similar). We see this when the ministry attempts to arrest Dumbledore.
We also know that Fawkes was "called" by the devotion that Harry showed to Dumbledore. So we can deduce that, rather than him flying from Dumbledore's ...
It didn't harm Ron because it did not hit him.
Ron was being menaced by a BIG acromantula. Ron saw Harry pull out his wand to help him. Ron helped Harry by leaning back on his seat. If you look carefully at the scene, you will clearly see him do this. Now Harry had a clear shot at close range. Young as he was, it was hard not to miss -- and he didn't.
The script (at least the copy) I found does not have Lucius saying anything at that point...
You shall not harm Harry Potter!
Dobby steps between and -- BANG! Malfoy flies backwards,
ands in a crumpled heap. Rising, he stares murderously
However, I can ...
The scene in the movie is an amalgamation of two seperate instances in the book during which Harry heard the mysterious voice. Finding Mrs. Norris takes place on Hallowe'en in the book, so all the other students are returning from the Feast, which is the reason they run into three constantly troublemaking students standing next to a recently ...
Because he is in the second year at Hogwarts, and that was the first ever time he had taken polyjuice potion, he was seeing whether his eyes were lying to him about the transformation.
As some potions can make you hallucinate, its sometimes best to use your sense of touch as well, because you don't know if your eyes are lying to you.
He probably also was ...
While Harry is the main character of the book series and movies and Dumbledore represents the height of wizarding excellence as well as the academic goals of Hogwarts, it's hard to argue that anyone else is the true heart of Hogwarts quite like Hagrid. He risks his life daily protecting the school, tending to creatures and would do anything for the students....
Based on the answer given to a somewhat similar question posted on SciFi a couple years back, they appear to be random:
Is there any significance to the licence plates on the Ford Anglia?
There is a link in one of the answers that shows the tag was the actual registration tag (the link is to a news story of the car being reported stolen from a studio lot).
I think if it can only be used on arachnids, why would it harm a human if it was aimed at a arachnid? If he said it with no arachnids around and just Ron, I expect it would leave Ron with the black scorch mark. This time it did not because there was an arachnid around.