recovery from command prompt starting from install dvd

In case of problems, I can use the vista installation dvd and select the
"recovery"options at the dvd startup.
One of these is the "command prompt" (dos style).

Wich is the command avaible in this window?
is there a guide (help) for the options I can use there?

For example I really appreciate the use of "bootsect.exe" to restore a vista
partition that was not booting anymore!
But I heard about this command from the internet .. what should I do without
an internet connection avaible?
none help typing "help" or "?" ...
where can I find an usefull documentation about?

thanks
Federico