Songs that I've sung to some effect in similar situations are ones that were popular anytime between 1890 and 1950. The older songs would have been sung to the older folks by their parents and grandparents, when the folks you're singing to were children. The more recent ones would have been part of the growing up of the younger folks you're singing to.

The particular songs will depend on your local traditions but, almost anywhere in Australia I can get favourable responses with "Two little girls in blue", Lavender Blue (almost anything in waltz time, in fact), stuff by G&S, etc, much of which (I suspect) would be part of the multicultural folks in your area.

Stories work best if they've some relevance to the folks themselves; sometimes the best stories are ones from your own experience. From (if not about) the heart. There's a lot of background to such activities so you'll find material in all sorts of places. Good Luck!

Cheers, Rowan