SharePoint 2010 External Authentication?

Hi,

I am looking to build a public web site on SharePoint 2010 Standard Server. I have an external SharePoint licence. It will be a publishing site that I implement. I will want the site to have anonymous access for the public to view and also a login page for internal staff to access in regards to maintaining the site. For authentication, what should I be using? Windows authentication through some sort of gateway like TMG or FBA? or Claims based authentication?

Thanks.