[Dovecot] Configure Dovecot For IMAP Only?

[Carlos Mennens]

I've install Dovecot 2.0.11-1 on my Linux server and all the guides
and tutorials I've found on Google don't work since I'm running 2.x
and it seems most guides were done with 1.x. I've opened up the
configuration file /etc/dovecot/dovecot.conf & from what I can see,
this is all I could come up with:

protocols = imap
listen = *
base_dir = /var/run/dovecot
login_greeting = Server ready.
mail_location = maildir:~/mail

I obviously want / need IMAP4 access ONLY and not POP3. I've got only
12 local Linux shell users and all authentication is done by I think
PAM. My friend sent me his configuration file to see if it would work
on Dovecot 2.x however I don't think it does:

auth_mechanisms = plain login
mail_location = maildir:~/mail
passdb {
  driver = pam
}
protocols = imap
service auth {
  unix_listener auth-client {
    group = postfix
    mode = 0660
    user = postfix
  }
  user = root
}
ssl_cert = </etc/ssl/certs/cert.pem
ssl_key = </etc/ssl/private/key.pem
userdb {
  driver = passwd
}
#protocol imap {
#  imap_client_workarounds = delay-newmail tb-extra-mailbox-sep
#}

Can anyone please tell me what I need to add to get this very basic
IMAP server up and running?