Personally, I think that you going for knoppix on the hard drive, is, (IMO) a good idea.
When I first started meddling with linux, I was mainly using mandrake, but I got delusions of grandeur. I'd heard so much about Debian (theres a small, but very vocal, if somewhat "tongue in cheek" minority at my LUG who expound the "Use Debian" message) so I got a copy of the stable version.
Whoooosh, as it all went over my head!
One of the vocal ones came over and installed it - I just didn't know enough to do that myself (actually the issue was mainly that the older stable kernel version didn't support my graphics card so he had to change it so that I had the unstable newer kernel). While I was meddling, I found that not only is Knoppix is derived from the unstable/testing debian versions, plus, it recognised all my hardware (including the graphics card) and figured that if it would do that from the CD, surely it should do that from the hard drive.
I was right. It was as easy, if not easier than installing mandrake, which IMO has very good hardware detection, but not as good as knoppix. It worked "a treat".
Sure, I can see the benefits of debian. Hell, have you seen the number of packages that it supports ? (10000 +)
Plus, if you do look into changing the apt-sources list so that it reflects "proper" debian sources, you'd never (in theory) have to install another distro. Just learn how to use the apt package manager. Brilliant - Ha!, that's one of the reasons that I changed to Gentoo, because that will do the same, the only difference being, that I download new packages/updates/upgrades as source code and gentoo then compiles it for my system and the customisations that I've chosen, whereas you'd just be downloading the pre-compiled binaries.
That, I suspect, is why Ubuntu has proved so popular since it's inception. Afterall, there used to be "Gnoppix" as well, which was a Gnome version of Knoppix - though that now seems to have been transformed into the Ubuntu Live version.
I, from choice, prefer KDE as my graphic windowing environment so wouldn't bother with Ubuntu or Gnome.
So "good on yer" for taking that route to get linux up and running. Theres a mountain of stuff at the knoppix site, so I've always thought that it's a good place for all sorts of Knoppix specific info.
The difference being, that LQ, you get a quicker response. Theres a hell of a lot more people here!
p.s. As for my site, well it's just my little corner of the web where I can shout and moan as much as I want! Then if anyone else wants to listen/read my rantings, its up to them.