I have the command "allhudtoggle" bound to me ] key, I believe the default is F4.

It's F4 as the default.

You might also need /hidelog to get rid of the chat. To get chat back, just do /hidelog again.

allhudtoggle hides the chat as well.

Well, there is no such command /allhudtoggle, and pressing F4 does not remove the chat =p

the command iirc is /HudToggle (my config is from a 3.2test i have zipped)

yoda, /hudtoggle removes only the hud. According to the default binding, pressing F4 removes all hud elements (hud and chat).

I don't have /allhudtoggle either. It's probably an alias for /hidelog and /hudtoggle that was added "recently". My config is pretty old too.

Oh hey, guess what, it is an alias, who would of thunk it!
For those who care:
alias allhudtoggle "hudtoggle2"
alias hudtoggle1 "HudToggle; hidelog; alias allhudtoggle hudtoggle2"
alias hudtoggle2 "HudToggle; hidelog; alias allhudtoggle hudtoggle1"

Also, I use another alias for taking screenshots of the ships in the buy ship menu, I use these to make things like:
http://lemming.localnetsys.com/wikithing/logo/

alias ss0 "dump ; wait 5 'ss1'"
alias ss1 "dump ; wait 5 'ss0'"