Kerberos is a very good security protocol but hard to implement because you need to have good knowledge in Active Directory and how Security works.
One of my colleagues who is our SME in that area comments on this Whitepaper as follows:
In my opinion this is the best documentation I have ever come across regarding Kerberos for SharePoint 2010. It also applies in part to MOSS 2007. I would recommend that we use this documentation as a guide on configuring Kerberos for SharePoint 2010.
Download it from here: Configuring Kerberos Authentication for Microsoft SharePoint 2010 Products
Or the Online version: http://technet.microsoft.com/en-us/library/ee806870.aspx