1. you start racking after the yeast are pretty much finished doing what they do. you can tell when this is through two different indicators. firstly, they will have eaten up all the sugar, so they will no longer be producing gas, so the bottle will stop getting super pressurized. basically when you open it to let the gas out, it's not a violent PSHHHHHHHHHHHHHHHH sort of thing, but more of a little fart.
also, the liquid will start getting fairly light and clear, except for the sediment at the bottom. think of something along the lines of apple juice or apple cider.
it gets to this point after 2 and a half or 3 weeks.
2. yes, it's possible, but it's not THAT big of a deal since the yeast have pretty much finished digesting the sugar, so they wont produce any vinegar at this point since they have no raw material to work with. when you do your racking stages just squeeze your bottles before you cap them so that the liquid is almost at the top and there isnt much air inside. it isnt that big of a deal though, you just want to avoid having a bunch of new air in there.
3. do the first rack, wait a day or two, do the second rack, wait a day or two, etc. you probably want to do 2 or 3 racks before you drink it. it'll start looking fairly clear. the gunk settles out pretty fast from what i can tell. essentially it's your call on how long you want to wait for the sediment to settle out, if you dont mind drinking fairly cloudy shit after the second rack, go for it. if you do plenty of racks though it still shouldn't take more than like a week and a half. so total brew time from start to finish is about a month. if you let it sit a week or two longer at the end the alcohol content will rise by a couple percentage points.
hope that fills you in, i gotta go to the library right now so i wont be around for an hour or so, tell me if you've got any more questions though.