Yes, unfortunately, there's a big difference. Aside from a variety of programs, the ability to choose either Gnome or KDE, there's also partitioning. The LiveCD will only install on a system where you can provide a relatively small (but at least 200 MB now, basically for use with future upgrades) /boot and an ext4 root.
The /boot partition must be ext2 or 3.
This has to do with the nature of the LiveCD, which is simply an image that will rewrite itself to the disk.
There was an announcement on Fedora forums or maybe I just did it as a sticky--I don't remember now, as it was awhile ago, but a lot of people were getting hit by the partition issue--about it. The DVD gives you complete flexibility with partitioning.
If you wish to install but only want to use one CD, the only way I've found to do it these days is to, when selecting packages, choose customize now and deselect everything, including Base. (If you don't uncheck base, there's some unnecessary dependency for either Gnome or KDE with polkit, but that's another issue.)
You will then have a very minimalistic text based system that has no X. However, it's easily populated afterwards with yum.
The additional advantage of doing it this way is that when you run your first yum upgrade, there's much less to upgrade.
Hope this helps.
