Trying to install R on Lucid Lynx

Hi:

I installed Lucid Lynx amd64 on my system today, dual booted with Win 7.
I've managed to install several packages through the Ubuntu Software
Center with success and also installed texlive. Alas, installing my favorite
software has not been so joyful. I went through the last few months
of posts in this group to find something similar, but to no avail.

After a couple of false starts, I found this web page:
http://blog.joelotz.net/?p=225
which seems to be doing the right thing and condenses some of the
information I saw elsewhere rather nicely.

I added the fhcrc site to the bottom of sources.list and copied all
the commands into my bash window. Everything is fine up to
sudo apt-get install r-base r-base-dev


I got the following response from the terminal:

dennis at dennis-PC:~$ sudo apt-get install r-base r-base-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
  build-essential dpatch dpkg-dev fakeroot g++ g++-4.4 gfortran gfortran-4.4
  libblas-dev libbz2-dev libjpeg62-dev liblapack-dev libncurses5-dev
  libpcre3-dev libpcrecpp0 libpng12-dev libreadline-dev libreadline6-dev
  libstdc++6-4.4-dev patch patchutils r-base-core r-base-html r-cran-boot
  r-cran-class r-cran-cluster r-cran-codetools r-cran-foreign
  r-cran-kernsmooth r-cran-lattice r-cran-mass r-cran-matrix r-cran-mgcv
  r-cran-nlme r-cran-nnet r-cran-rpart r-cran-spatial r-cran-survival
  r-doc-html r-recommended xz-utils zlib1g-dev
Suggested packages:
  curl debian-keyring debian-maintainers g++-multilib g++-4.4-multilib
  gcc-4.4-doc libstdc++6-4.4-dbg gfortran-multilib gfortran-doc
  gfortran-4.4-multilib gfortran-4.4-doc libgfortran3-dbg libstdc++6-4.4-doc
  diffutils-doc ess r-doc-info r-doc-pdf r-mathlib cdbs debhelper
The following NEW packages will be installed:
  build-essential dpatch dpkg-dev fakeroot g++ g++-4.4 gfortran gfortran-4.4
  libblas-dev libbz2-dev libjpeg62-dev liblapack-dev libncurses5-dev
  libpcre3-dev libpcrecpp0 libpng12-dev libreadline-dev libreadline6-dev
  libstdc++6-4.4-dev patch patchutils r-base r-base-core r-base-dev
  r-base-html r-cran-boot r-cran-class r-cran-cluster r-cran-codetools
  r-cran-foreign r-cran-kernsmooth r-cran-lattice r-cran-mass r-cran-matrix
  r-cran-mgcv r-cran-nlme r-cran-nnet r-cran-rpart r-cran-spatial
  r-cran-survival r-doc-html r-recommended xz-utils zlib1g-dev
0 upgraded, 44 newly installed, 0 to remove and 0 not upgraded.
Need to get 0B/47.1MB of archives.
After this operation, 115MB of additional disk space will be used.
Do you want to continue [Y/n]?
Media change: please insert the disc labeled
 'Ubuntu 10.04.1 LTS _Lucid Lynx_ - Release amd64 (20100816.1)'
in the drive '/cdrom/' and press enter

at which point the shell hangs after entering.

I installed Ubuntu from a bootable CD-ROM this morning, using

http://www.dedoimedo.com/computers/dual-boot-windows-7-ubuntu.html

as a guide, particularly for setting up the file system. Because I have a
Dell,
three primary partitions were already taken up. I took about 450Gb off my
hard drive for Ubuntu and created the fourth partition for it as shown in
the link
above. I don't know if it has any bearing on the present problem, but
in case it does...


I've gotten the same response in the shell after each of four attempts,
including two where I only asked to install r-base...at least the error is
repeatable :) I'm hoping to find a way to get R installed in the 'usual'
way.

I'm an utter newbie in Linux so you may have to talk slow-ly to me.

TIA for any help.

Dennis