Fix for mouse : need help understanding basics

[Lee Gold]

Using Fbsd 4.4. A fix I want to apply per the FAQ calls for,

  boot: -c
  userconfig> flags psm0 0x100
  userconfig> quit

I see how to get to this boot: prompt during my routine booting-up -
I interrupt booting w/a <space>. 

ques:
1. what is this feature called? i.e.. when we are booting and
    hit a space or "\" etc. we get a menu and typing "?" gives
    many options. What is this 'pre-boot feature' called? Is
    there a man or help links for it?

2. Same for userconfig, what is userconfig doing and what will
    the string I enter at the userconfig prompt do? Tried to find 
    docs on userconfig, but docs are for the Fbsd install program
    which seems to have the same name.

3. Will the fix cited above be permanent if I shutdown then reboot?
    If not can I make it so?

Thanks