caker's Debian distro is pretty minimalist - lots of us use it as an emergency spare to boot into when we ned to work on our main systems without the filesystems being mounted.
If you choose Debian, you have to use apt-get to install your choice of software.
If you choose one of the full distros (Redhat 9, Mandrake 9.1), pretty much everything is installed - it just needs to be configured to suit your requirements. However, they take up a lot of disk - 1.7 GiB for RH9 vs 80 MiB for Debian before you add to it.
If I were just starting out, I would choose Debian and install just what I needed. Check out
Harry Sufehmi's Debian Linode tutorial plus the discussion
here.