It's usually one question = one thread here and dead threads aren't revived, although I don't beleive that these are official rules as much as conveniences.
I'm fairly sure that I saw an option for configuring network logins during the SUSE 8.2 installation process (which is just YaST in a different mode). On Linux authentication is handled by a system called PAM, which has plug-ins. Applications query PAM, which can be configured to get the authentication information from a file or a network service, and other plug-ins do other jobs. The distribution-specific client tools just configure PAM, and that's the easiest way to configure the system to use either an LDAP or Kerberos service for authentication.
Kerberos can authenticate username/passwords from a database, or (more commonly) get the information from your LDAP service. An advantage of going through Kerberos rather than using LDAP directly is single-sign on for the whole domain: once authenticated with Kerberos a ticket is cached, so you shouldn't get pestered again for a username and password by applications that support Kerberos.
Having looked at the SUSE 8.2 manual again, it shows you how to configure Kerberos on SUSE, but doesn't tell you how to set up the LDAP service :-(
The best on-line resource that I've seen is the OpenLDAP documentation on www.openldap.org.
PHPLDAPAdmin seems popular as an interface for managing LDAP once you're got it running.