LinuxQuestions.org - apt-get install dependency problems with hplip software and kde install for Agnula

Hi,
I'm using Debian from an Agnula distribution (Linux demudi 2.6.12-3-multimedia-k7) and have been having some problems with apt-get install. I have been attempting to install hplip software for my new printer and it gives me dependency problems, a guy from hplip reckoned my sources.list might be wrong (below):

#deb file:///cdrom/ sarge main

deb cdrom:[Debian GNU/Linux A/DeMuDi 1.2.1 _Sarge_ - Unofficial i386 Binary-1 (20050627)]/ unstable main

# Security updates
#deb http://demudi.agnula.org/packages/demudi demudi main/updates

# Bleeding-edge packages
#deb http://demudi.agnula.org/packages/demudi demudi main

# Debian official archive
# deb http://ftp.debian.org/debian testing main

#See sources.list(5) for more information
deb http://http.us.debian.org/debian stable main contrib non-free
deb http://non-us.debian.org/debian-non-US stable/non-US main contrib non-free
deb http://security.debian.org stable/updates main contrib non-free

The install.log gives this problem:
The following packages have unmet dependencies:
libcupsys2-dev: Depends: libcupsys2-gnutls10 (= 1.1.23-10sarge1) but 1.1.23-10 is to be installed
Depends: libgnutls11-dev but it is not going to be installed
libsnmp5-dev: Depends: libssl-dev but it is not going to be installed
python-dev: Depends: python2.3-dev (>= 2.3.4-18) but it is not going to be installed
E: Broken packages

I have also tried running # apt-get install kde

and get the following which is also annoying (although I do like gnome I would like a choice.)
Reading Package Lists... Done
Building Dependency Tree... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.

Since you only requested a single operation it is extremely likely that
the package is simply not installable and a bug report against
that package should be filed.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
kde: Depends: kde-core but it is not going to be installed
Depends: kde-amusements but it is not going to be installed
Depends: kdeaddons but it is not going to be installed
Depends: kdeartwork but it is not going to be installed
Depends: kdegraphics but it is not going to be installed
Depends: kdemultimedia but it is not going to be installed
Depends: kdenetwork but it is not going to be installed
E: Broken packages