You could use concrete screws to fasten in nail to hang pictures
You can use 3M Command strips to hang decorations without harming the wall.
You can buy special wall anchors for concrete. Ask the hardware pros at the home improvement store for advice.
Hi Margaret! It is a challenge but once you get your plan together you will be happy with the results. I painted my basement in a pale green/white & put up large pieces of wood (peg board) and hung things on that which looks really nice. On another wall I put up a mural which is lovely. Take a look at these sites for more ideas!
I use two-sided tape on painted cinder block walls. I used embroidery hoops and old thrift store picture frames, and just covered them with fabric. It looks great.