help: email server

[Marcelo Chiapparini <chiappa@uerj.br>]

Hello,

I need some help from the list!
I am in charge of a pos-graduate program and I need to set a server to 
host the following stuff:

a) the Program web page
b) the Program email account
c) the students email accounts
d) webmail 
a) b) c) should be accesible from the Institution's intranet and from 
dial-up connections. Option d) is for manage the emais when people are 
travelling.

1) Where can I start to read about this?
2) Can I use Debian or FreeSDB is better?
3) What firewall and webmail programs are good?
4) Can the server host the firewall too?

Thanks in advance for the help

Marcelo

--
Marcelo Chiapparini
DFT-IF/UERJ
chiappa@uerj.br