I've been involved in lots of shows juries over the years. One of the biggest jobs involving shows is keeping all the entries sorted.
Even within strict parameter rules for entry, things come to jury committees in many forms and one must be meticulous about handling all the material. Some work gets submitted in the most appalling manner.
When you send digital entries, be sure to label the CD exactly as they request. And, as mentioned previously, be sure to use a special pen for writing on disks. If no special format is requested, I always do this anyway. Your name, the show or entry title, the date and any other brief information is enough.
In addition, I compose a paper thumbnail label with the same information to slip inside the jewelbox. Then I make a large CD label that fits into the front of the box.
Most printers will do CD label sizes. If not, figure out the size, print it off and cut with scissors to fit.
The name of the show, your name, mailing address (omitted in the example), phone number and email address and any other information that might be needed should go on the label. If there is any question about your entry, it will be easy for the show committee to get in contact. Your job is to make it as easy as possible to for the jury and committee. Choose a regular disk--not the more expensive read/write kind for your submission.
Don't send a huge, gazillion-pixel image. Stay within the image size they request. They don't want to have to fiddle with your entry. They don't have the time or possibly the computer capacity to handle huge shots.