The familiar place(s) could be somewhere that you've actually been, or it could be so that you're comfortable with other things happening within the dream. So, there may be a tie to the place(s) or maybe not. As for the deceased people, I'm really thinking they are trying to get through to you, to contact you, to tell you something.
I'm about to say something cliche... keep a notepad and a pen/pencil next to you when you sleep. Then, immediately, before doing ANYTHING else, write down what you can remember. If you wake up multiple times during 1 sleep period, do it each time. If you can jot down something, anything, it should help you to figure out what is being conveyed to you in the dream, whether it's a message from them, or if it's another type of message that you need to pay attention to.