After removing the DVD and hitting enter, the system should have rebooted. If it did this, and then eventually gets to the dcerouter login prompt but does not go any further then you may have an issue with X not starting. Generally, if X doesn't start, then if you sit there and watch the dcerouter prompt it will occasionally flicker, go to a black screen, then come back, again and again... this is X trying to start up but failing.
If this describes your symptoms, then you should try reading through the X log, here /var/log/Xorg.0.log as it will list the reason why it is failing. Often you need to update the driver. You can either ssh into the box from another machine, or reboot the core and when you get to the GRUB start menu it gives you 2 seconds to hit ESC and then you can choose recovery mode to get a command line. From the command line, review that log file and see where it fails. If you need to update your driver, you can do it from the recovery mode by following the Display Drivers article on the wiki.