When I tried to install debian, it was "MEGA" hassle. I couldn't startx it wouldn't let me config my graphics card - I found out that it's because the driver for it is openly available, but not gpl and hence not included with woody (also the driver would only work with a 2.4.xx kernel, and not the default 2.2.xx kernel that I'd installed with woody).
I did eventually sort this out, but as I'm a bit of a glutton for punishment, and never managed to get the graphic interface looking anywhere as near as nice as the default mandrake system I'm used to, I cheated.
The cheat - well, if you found that everything (well nearly everything) worked with knoppix from a cd then the cheat is to just install the knoppix cd to your hard drive - it becomes a debian unstable/testing install (basically) and don't forget that debian developers are pretty conservative people - it takes ages to have an "unstable" package moved to "stable" - the unstable and testing might have a few minor "hiccups", but are very much more up to date than stable debian. (if it worked from a knoppix cd, it should work from your hard drive!)
If you did install the knoppix to hard drive, you will find that it is nearly as easy as a mandrake install. Have a good look through the knoppix forums
, you should be able to find all the stuff you need there - then just follow instructions for debian unstable.
You would have to do a few things like creating a proper user account, proper root and passwords, but from memory, that's pretty straight forward.