LAN connection problem.

[Nightmare]

sorry for all the bothering but here are the questions.

1. when i configure my network cars, i use the knoppix network card setting and it gets my ip address from the main server.
however when i tried to connect to internet (and i have configured my proxy settings and set it to prompt for password and username) it just shows up that i do not have any authentication. (just like when i do not type my user name and password on windows xp.) is it to do with school blocking any other access other then windows, or is it to do with my settings?

2. my school uses a network and it is quite massive.
the main dns server is 'cc' and i use net1 as the internet server.
when i use internet explorer on windows XP, i type 'cc\XXX' (XXX is username example) then type my password,
which let's me use the internet. now, how do i connect to the internet using konqueror or mozilla?

sorry for bothering and i apologise if you do not understand the question.
(but i have done my best to describe the problem so i hope this will be enough for people to understand)