apt-get question

[Eric Richardson <eric@milagrosoft.com>]

Hi,
I loaded standard potato. During installation I did some apt-get setup.
The setup put a line like the following sources.list:

deb cdrom:...
 three lines, one for each cd

deb ftp:/...   potato main non-free contrib
deb-src ...    potato/non-US
and two other lines.

The distro comes with the following lines:

deb http://...  stable main ...
deb http://security.debian.org  stable/updates

Here are the questions.

1. Does the order matter? Will it look to cd first if the cd entry is
first in the file and then online second?
2. My setup says potato but should it say stable? Does this have the
consequence that if testing becomes stable I would get an upgrade? With
potato in the file will no upgrade occur?
3. I want the security updates so is the default entry fine?
4. I should be at version 2.2r2 as I did an update from r0. Should the
kernel be 2.2.18 as it seems this is in the proposed changes or should I
stick with 2.2.17?

I know these questions are basic but thanks for the help.

Eric :-)