go around to some of the places you have visited and collect leaflet, postcards, menus, brochure etc of them, such as the fair, the zoo, museum, a local pub, club, a restaurant etc
you could also make a collage of all her favourite old pop stars, film stars etc over the years, also including her favourite films, songs etc with album covers and film posters - you can print all these off the net
or instead of a collage, you could also make her a calendar with the images on it.
on your printing/scanner software there will probably be an option to print your own calnedar - you just insert your own pics and the software will sort the dates etc - then you just print it out - she will be reminded of your memory box every month when she turns the page.
you could find a charicaturist artist, give them some pics and ask them to create a jokey scenario based on a real experience you have enjoyed, using your faces.
- my sis went to scotland and got one done of her and her boyf - he was in kilt standing over the loch ness with nessie peeking out, but they should be able to create anything you like.