Any Highlander fans out there? I have some questions.

[thefourthvine]

Do you know HL? I need some help from people who have seen Highlander canon. Here's what I'd like to know:

1. What are all the ways to permanently kill an immortal? I know cutting off heads, but is there anything else? And is it different the first time they die? And does it matter if the whole head doesn't come off - like, can they come back if the neck is only mostly severed?
   
   
2. What happens the first time they (don't) die? I mean, they think they're mortal for a period of time, right? And then they die, except they don't, and they say, "Whoa, dude. I must be immortal, because that sure as shit should've killed me." (Although I think most people would assume the injury or whatever just hadn't been as bad as they thought, so - do some of them have to die a lot before they figure it out?) But I'm a little foggy on the whole deal, frankly. Do they have to be buried and then rise again, like vampires? Or is it more of an instantaneous thing?
   
   
3. What happens if you shoot an immortal (who has already done the first not-death, if that matters) in a way that would kill a human but won't kill him? (Like, gaping chest wound, something like that.) I'm pretty sure he has at least a period of, shall we say, limited activity, but how long is he down for? And exactly how limited is his activity? And what happens - like, do the wounds visibly close over and heal, or does he just suddenly sit up all better, or what?

As much detail as you've got, that's how much I'd like.

And if you know any sources for getting this kind of information without bugging my friends list - like, a Highlander encyclopedia or whatever - I would love to know about it.