You are well within your rights to create the files to reproduce the cab art for your own game. I believe the "technical" name is "the right to restore" for a machine you own. Similar to the copyright of a DVD (movie or game) - you are well withing your rights to reproduce a BACKUP copy for your own use as long as you still own the original copy.
I'm sure someone might know the "exact" wording, so I'm interested to hear if I am close.