dhcp et dns sous mandriva (linux)

hello every body, i have a half-project for my studies, its a intranet in my compus, (unuviersit?) so i find deicult to make in a dhcp with dynamyque dns ?
Q1 – how can i start to do it?
Q2 -mmust i turn the PC (OS) on root ?
if yes ( in my distrubution mandriva i can’t enter with root) even the root and password is true ?!
thnks eevry body
waiting for your helps