First of all good work on the back-up!!
If any of you have made copies that can only be used via your cdwriter that means that your writer is not full compatible -OR- the cd's that you are are not accepting the image correctly... -OR- both..there are other factors but it seems like you have looked at them already. Remember..the quality of the CD/R or CD/RW that you are using are just as important as the type of drive that you are using. I have had 100% success with Memorex 700mb CD/R's and /RW's. Also, if you are using CloneCd and your drive says that it is not compatible with 700mb drives disregard that information..it is the program that came with your drive that is not compatible..not your drive!!!
Happy New Year!!
Cybercop 8)