I think it would be very helpful if there was a Next and a Previous button on the Profile/Image Comparison screen. This would help when reviewing a large list of changes by avoiding the need to constantly return to the "Refresh Updated DVD Profiles" dialog.

Another accelerator would be a synchronized scroll between the two panes (Existing & New DVD Profile/Image) - you would need either a preferences option or a check box on the comparison screen so the sync could be turned off when needed.

Final suggestion would be upon first opening the comparison screen to give focus to the either the synchronized panes or just the New pane (when sync is off) so that the page up/page down and cursor keys would work.