a simple solution to prevent xdm from starting everytime you boot is to
remove xdm from /etc/rc2.d. See, whenever linux boots it runs a script that
causes the files in /etc/rcN.d where N is a number between 1 and 6 (called
runlevels). Debian is set to runlevel 2 by default so by removing xdm from
the directory executed in runlevel 2 you stop xdm from running at startup.
This is a pretty crude way of doing it compared to some stuff that was
discussed earlier this week, but its what i did and it works fine. As to how
you can boot successfully to do this in the firstplace, you need to be in
runlevel 1, which is single user mode and doesn't start xdm, and i'm not sure
how to do this short of having a specially prepared boot floppy (yea, i'm
pretty new to this myself) but it doesn't sound like you have a big problem
with re-installing sooo, you might try that, and removing xdm from runlevel 2
right from the start.
(anyone who happens to read this, please look for MY XF86Setup question, as
i'm really having some trouble with it, thanks)
