Quote - DVD might be safer.
I lost an external hard drive and found out that they tent to overheat.
fortunately I did recover most of the file on it but still can't  recover the boot sector.
And I thought it the best, safest way to backup.

The one I have used to get very hot too.
Almost burn me if I touched it.
What I did was get some heat sinks
(those little aluminum things with the
fins on them) and stick them on the
drive with some heat sink compound.
You can buy these at a electronics
supply store if you aren't familiar with
them.  Now the drive is barely warm.