When a call is blocked the call is disconnected by default, meaning that the incoming call is terminated without ringing. You can also choose to send blocked calls to voicemail.  You should not hear a single ring when the call is disconnected, though sometimes depending on your home's telephone configuration you may here a ring in rare circumstances.

The calling party will hear one or two rings and then the call will be disconnected, as if you hung up on them.  They won't get access to your voicemail (unless that's how you've configured Call Control to handle blocked calls).

You'll have full transparency to see all of the calls which have been blocked.  Call Control Home will display all of your recent call history, including any calls that have been blocked, so that you can audit and view the blocked calls to know which calls have been blocked.