Fedora Core comes with the ssh server (sshd) installed by default, but I don't believe it is enabled on boot-time. Non-encrypted telnet shouldn't be used at all since ssh can do everything telnet can and more.
The mother of all port scanners, nmap, is included with Fedora as well but I don't think it is installed unless you select it during installation. You can of course install it from the CD's or download the source (from
http://insecure.org/nmap) and build it.
Håkan