Please help with permissions problem

[Scott Ehrlich <scott@ehrlichtronics.com>]

Whenever I install a new Debian Woody system, create a normal user
account, then log in as that user, some X-based (and maybe some non-X, but
I don't recall right now) programs work fine, while others require sudo
access.

One example is Mozilla via apt-get.  I discovered kword works fine.  I
performed a permissions and owner/group comparison of mozilla-1.0.0 to
/usr/bin/kword and found both to be the same.  What actually happens is I
start Mozilla with just typing mozilla, for example, and it will try to
start, then fail.  Another example is X.  I set KDE as my window manager,
type startx, and get a warning in the standard X background before the
window manager kicks in that KDE does not have permission to write to
/home/scott/.ICEauthority and get dumped back to my tty console.  I redo
this with sudo startx and all works fine.

What am I missing?

I would love to finally know the solution, as I am likely going to convert
my home setup to Debian w/X from Windows.  Learning the answer will also
let me fix the same issues for people at work who have installed Debian on
their laptops.

Thanks for any pointers.

Scott