I just got my hands on the new Debian 7 DVDs and installed a fresh server install. Now up and running its time to use aptitude to install some software when I kept receiving the following message:

Media change: please insert the disc labeled ‘Debian GNU/Linux 7.0.0 _Wheezy_ – Official amd64 DVD Binary-1 20130504-14:44’ in the drive ‘/media/cdrom/’ and press enter

Fixing this was a simple task. All that was needed was to remove or comment the reference to the CD/DVD from the /etc/apt/sources.list

Example: #deb cdrom:[Debian GNU/Linux 7.0.0 _Wheezy_ – Official amd64 DVD Binary-1 20130$

steps are:
log into your debian system
sudo nano /etc/apt/sources.list – sudo if you are not logged in as root
#comment out the line in the above example – saving the file (ctrl x) enter y for yes