If you have made your backup using the extreme method have you made sure that you've added a video partiton?
If it is an Xtreme method backup then I would suggest using IsoBuilder and burning with CloneCD because I've found this to be a very reliable way to make a backup.
If your wanting to use ImgBurn then you wont be able to use IsoBuilder unless you've got a working backup that can get a video partition from because IsoBuilder just adds a blanked out video partition and ImgBurn doesn't like this (as you will see in the ImgBurn tutorial).
Also quite a few people get better quality burns setting their burning app to burn at the Maximum speed. If your +R DL media only supports burning at 2.4x on the second layer then your burner will cut the speed of your burn to suit.
It doesn't matter that the image is called image.000 with either ImgBurn or CloneCD as long as your .dvd file has the correct info for the program your using, which if you're using ImgBurn it should just say "image.000" (without the quotation marks)
If you find that you like using IsoBuilder and want to use ImgBurn to burn it then you'll need to get a working video partition by following the steps in the ImgBurn tutorial (trust me IsoBuilder is very good and simple to use, you just need to call your backup or dump "game.iso", your ss file "ss.bin" and make sure they're in the same folder as the build360.bat and it will give you a perfect working image).
Once you've got your working video partition you can then replace the blank360.iso in the IsoBuilder/Xbox 360 directory (just call your new video partiton blank360.iso, the steps are in the ImgBurn tutorial)
If you follow the steps in Geebee's latest tutorial v35, which can be found
here and use the recommended steps and programs then not much can go wrong.
Just make sure you understand it and follow all of the steps.
I would also suggest that if your burner supports CloneCD and you have it available, make your first backup following the IsoBuilder/CloneCD method and you can be certain that you'll have a good working image ready to burn (there's nothing that can go wrong if you make sure your files are the right names, game.iso. ss.bin, then run build360.bat and burn with CloneCD).
If this doesn't work for you then I'd think you've got a bad flash and or if you've got a Hitachi it may be having trouble reading backups, because IsoBuilder puts everything where it should be.
Sorry about the length of the post mate but I wanted to be as clear as possible 'cause there's quite a few steps you can make a mistake in if your not careful. Anyways I hope this helps