Many thanks, I have also read the guide you provided also cynthia (I will definitely download the soft when I get home later) and start checking discs.
I understand pretty much everything I have read, (Really Interesting!!!) except the numbers on the left hand side of the graphs, are they related to the relevant PIF / PIE readings? If so I can't quite see how they are related. e.g taking the first graph above posted by Lighting U.K., the Avg PIE reading is displayed as 2.0 (which is amazing) but looking at the mean average of the graph on the left hand side I would say it was closer to 7 or 8, there is even a spike on the graph where it hits 15.
Also would it be more thorough to verify my discs with opti drive from now on rather than imgburn.
UPDATE: I checked most of my x360 backups yesterday using Opti Drive on my Optiarc AD-7583s laptop drive but it keeps giving me the error code 31105, the discs are not scratched and they are all written to verbatim media using Imgburn and were verified, these checks have shown them to be good burns.