First its no long "Fedora Core" its just "Fedora" starting with 7.
Now that we have that cleared up, you might be interested in a CD based Distro or the LIVE CD version of Fedora 7 in either KDE or GNOME.
If your looking to dual-boot and new to Linux, your really better off with Ubuntu or PCLinuxOS. Ubuntu even has migrating tools to move your XP users to Linux.
Also check out wubi
This is perfect for XP users who can't or don't know how or just don't want to burn an ISO of a CD.
Hope that helps