Login for viewers – not for admin

I need to use WP as a CMS for a client’s website. This client wants a welcome page with a customized welcome message, but everything beyond that password protected. I don’t want to password-protect each page and have members need to log in repeatedly. I also need to be able to have a log-out feature. The plugins I’ve tried seem to be for logging in to the admin panel – not what I want. I need to have those wanting to enter the site as viewers to be required to log in. (The client will be giving passwords out to those who join his group.)

I’d welcome suggestions for good plugins – I know that it may take more than one to accomplish all of these goals.