newbie: Help, I'm stuck!

[Scott Frankel <leknarf@pacbell.net>]

  Problem 1: the cursor won't respond

I installed the Potato release as the default OS in a dual-boot
setup on an Apple PowerBook "Pismo" (Firewire/2000/&tc.).  X (v.3)
launches happily, but the cursor arrow won't respond to either the
trackpad or an externally connected USB mouse.  It won't budge from
the center of the display (which is some sort of Debian desktop
decoration with some icons on either side.  Don't know what they do
yet; I can't click'em.)

I've tried manually editing the XF86Config file, setting the pointer
to /dev/input/mice, as per a suggestion.  Still no joy.  In searching
the new system & documentation for an X configuration tool, I found
that none were installed (I chose the "task-based", "simple" installation
method, selecting everything I *thought* would be useful).  This leads
to:

  Problem 2: dselect config file mulched

I've inadvertantly hoarked whatever shoot-myself-in-the-foot.config
file it is that controls what the dselect program can access.  I can't
seem to get a package list update from the CD's I installed from.
With this remedied, maybe I could install the man pages!  In any event,
this leads to the frustrating:

  Problem 3: dsl via dhcp internet connection does't work

Which means that I can't connect to the Debian ftp site to download the
XF86Setup package!

I posted a plea the other day and received very interesting information 
in return.  (Thanks!)  My /etc/network/interfaces file, edited accordingly,
now reads:

    # interfaces to launch at boot
    auto lo eth0

    # loopback interface
    iface lo inet loopback

    # fast ethernet
    iface eht0 inet dhcp

Nontheless, I still get "unresolved address" errors from dselect's Access
methods.  Lynx complains as well.  From a cold boot and root login, invoking
"ifconfig" returns no output whatsoever.  If I then invoke 
	% ifconfig eth0 up
I get 
	eth0 PHY ID: ... 
	full_duplex:1, speed: 100

dselect & lynx remain unhappy though, even after that ifconfigery.  Note that
the computer is connected to a Linksys Cable/DSL Router, which serves IP numbers
via DHCP -- and the whole setup works flawlessly under MacOS ...

Two related questions:  
- What does /sbin/pump do?  I'm told it plays/can play a role in dhcp
  configuration.  What would/should I do to implement it?

- What does /sbin/ifup do?  There's reference to it in the original 
  /etc/network/interface file.

Thanks in advance for your help.  I've spent the better part of a week absolutely
dead in the water -

Scott