Photographs are a great,  low cost way to personalize your decor. Here are some suggestions:

Use a theme. For example, use pictures of several generations' weddings and put them in various sizes of vintage frames to display in your dining room or bedroom. Graduation pictures work well too. Or consider pictures of family members when they were all at the same age(one year old is a fun picture)

Got beach decor in your bathroom? Use a collage of your family's tropical vacations to decorate one wall. This is great in a laundry room or mud room too.

Hang black and white family photos in various sizes in an entryway or long hallway as a decorating element. Using all back frames of different materials adds to the drama of this display. Don't get bogged down with hanging frames in a straight line. Hang them at varying heights to add another dimension to the display.

Lean a large family photo against a wall on a mantel or tabletop, instead of hanging it. Consider using a vintage family photo and surrounding it with items from that era.

Copy an old photo , put it in a deep unique frame(the bigger, the better) and use it for a serving tray. It makes a great centerpiece along side a coordinating candleholder.

Display photos from a chandelier. String a lightweight chain or beaded trim around the light fixture. Use curtain ring clips to hang photos from the chain. Get creative with the clips. Change the display with the seasons. At Christmas, hang photos from past Christmas'..you get the idea.

Visit Accents in a box for more unique home decor items.