I think Vickya's suggestion is a really good one. I visit my Auntie and when we talk about recent things, she gets very confused but when we looked at some photos, it seemed her mind clicked back in and her memories of the past were sharp and her face lit up as she remembered people and places. Our local paper used to ask people to send in photos of our area from the past and being in a library, I'm pretty sure there must be literature of that type you could choose and hand around. You could also get in touch with a care home and find out from the staff there what their residents who have dementia enjoy. The exercise thing Vickya suggested is a good idea too. Keep them a little active. What a lovely thing to do, for sufferers and carers respite. I wish you every success.