I never bother with either "fandom" or "disclaimer", the first because I've only ever written for one fandom, and everybody on my flist knows that. If I branched out, I certainly would, though probably in the subject line, rather than the header itself. Disclaimer, I can't be arsed. Torchwood itself seems to be pretty (a) aware of fic and (b) unlikely to go after anyone for it, and I can't see that a disclaimer would help if it did.
As for A/N and the beginning vs. the end, I use both. If it's something I want readers to know off the bat - betas, for example - it goes at the top. If it's a question about their thoughts that might give stuff away, I put it at the bottom, and same with general chat about writing the chapter, since I don't want to hand out preconceptions before they dive in.
I use everything else, though if, for example, I'm posting to a specific pairing's comm, I won't put in the main pairing. I don't write things that require warnings, so I don't tend to need that, but I like it on other people's fics, not because I'm easily squicked but because I want to know if a fic has a kink of mine in it, because I'm more likely to click on it.
no subject
I never bother with either "fandom" or "disclaimer", the first because I've only ever written for one fandom, and everybody on my flist knows that. If I branched out, I certainly would, though probably in the subject line, rather than the header itself. Disclaimer, I can't be arsed. Torchwood itself seems to be pretty (a) aware of fic and (b) unlikely to go after anyone for it, and I can't see that a disclaimer would help if it did.
As for A/N and the beginning vs. the end, I use both. If it's something I want readers to know off the bat - betas, for example - it goes at the top. If it's a question about their thoughts that might give stuff away, I put it at the bottom, and same with general chat about writing the chapter, since I don't want to hand out preconceptions before they dive in.
I use everything else, though if, for example, I'm posting to a specific pairing's comm, I won't put in the main pairing. I don't write things that require warnings, so I don't tend to need that, but I like it on other people's fics, not because I'm easily squicked but because I want to know if a fic has a kink of mine in it, because I'm more likely to click on it.