I've never really used xinetd; but here's some guesses based on what I know:

> What is the best way to remove particular xinetd services from a box?  I can 
> turn the service off, but would prefer to remove them entirely.
	delete the file for the service in /etc/xinetd.d/
 
> Can someone enlighten me on why certain services are run out of xinetd.d
> vs init.d?  Or point me to a URL explaining.  Thank you.
	init.d is for daemons. xinetd replaces inetd; which is a
'super-daemon', which starts an instance of a service when someone makes a
request for it.
	so if you didn't want to spend the memory and CPU  resources to
keep an FTP daemon running; you could just run it out of inetd/xinetd, and a
process for it would only be started on those occasions when someone
requests it.
	inetd/xinetd also use the 'tcpwrappers' library to control access to
services; so you can put entries in /etc/hosts.allow and /etc/hosts.deny to
allow or deny requests for those services that the super-daemon controls.
(much easier than ipchains/iptables; tho not as universally useful).
	you can also play tricks like putting the following line in your
/etc/inetd.conf file:
telnet stream  tcp     nowait  root    /usr/sbin/tcpd  /bin/cat /dev/urandom
	which will cause a stream of random characters to be spewed at
anyone who tries telnetting to your box. :)
	I'm sure there's a similar thing to do for xinetd.

Carl Soderstrom
-- 
Network Engineer
Real-Time Enterprises
(952) 943-8700