Discs Are Being Burnt Corrupt?

First of all, I apologise if this is the wrong forum, but I don't know where the cause of this problem lies.I have a Windows 7 64 bit PC which until recently was working fine, including burning data DVDs (ebooks, zip files, text files, etc). ABout a week or two back, though, the discs I burnt began to turn out corrupt, with Nero reporting errors when verifying the discs. Whenever I reformat my PC and install the drivers and programs I make a disc image of the C: drive, so that I can reapply this image back to the drive at any point in the future, effectively rolling back the hard drive to the day when I reformatted and reinstalled everthing, so I applied the image to the C: drive, thinking that this would cure whatever file corruption was causing Nero to burn corrupt discs.

This failed to cure the problem, so I assumed that the DVD drive was failing, so I bought a new one, which exhibited the same problem. I tried other software (CDBurnerXP and Ashampoo) and they produced the same corrupted discs (some of the files on the disc had errors, just like with Nero, but the data on the hard drives itself was fine). So I tried burning a virtual disc image from Nero, and it turns out that the disc images Nero makes have the same corruption (which staggered me, as if the problem is purely software then I'd have thought that when I applied the C: drive backup image over the C: drive that would have solved the problem). Someone suggested it might be a rootklit, hiding in the boot block of the drive (I'm not well up on drive fundamentals, can a virus/rootkit hide in the bootblock and escape a C: drive re-imaging?) so I tried Combofix and others, and Combofix detected some 'suspicious' items and deleted them, but the problem still persists.

I tried four seperate Linux boot discs, as that way I could bypass the hard drives totally, so if I got the same error with Linux then I'd know the problem was hardware based, but Ubuntu, Mint, and Mageia all stuck mid-boot, whereas I managed to get Puppy linux to work via it's VESA setting, but the burner software in Puppy Linux (when I'd finally worked out that I had to mount the Windows 7 drive for the data, and how to then find the drive in the file system) just threw up an error - I can't remember what the error was now, I'll post it up when I get home later). I'm a *total* beginner to Linux, so please can anyone help me to get Ubuntu etc to load, so I can burn a DVD using Linux, to see if it's a hardware or software cause of the DVD-R data corruption?

Anyway, I removed all three of my hard drives, inserted an old IDE drive that had never been in a PC before, formatted it, and installed Windows 7 and Nero, and it too produced corrupted virtual disc files, and I'm 99.999% certain that no malware/rootkit could have infect that new (to the PC) hard drive, so I think the problem here is hardware, but I'm not sure.