Agree with contacting an expert. If you watch the Antiques Roadshow, you will see how sometimes people ruin the antique quality of an item, or ruin the the piece itself by washing it incorrectly. The flag probably needs a gentle wash and rinse. I would display it on July 4 and Veterans Day, and otherwise keep it tucked away. I think the other memoribilia would be nice in a display box, but if you display it year round, some of those things will become damaged by the light. Display it during July or during family get togethers and otherwise keep it in the dark.