I've got a little problem.
I've found out that the old DVD-ROM drive in my server doesn't actually want to read DVDs anymore... or at least, it doesn't want to read the Knoppix DVD I burnt. I'm not quite sure what's wrong with the DVD (since my burner can read it, but at least two other regular drives can't), but I'm thinking that the DVD-ROM would probably not read a proper DVD anyway.

So I've got a few questions, which hopefully haven't been asked already (I didn't see them in searches):
- Would it be possible to take the images out of the DVD ISO, and burn it as a CD, then boot off the harddrive? (Where I prefer to keep the images anyway, since I have the space.)
- Failing this, can a previous version (say, 3.8/3.9) boot a 4.0 image? I read/heard somewhere that this isn't possible, but I'm hoping some method is.