After reading the whole thread, I think I finally understand what is going on.
/etc/services really is only for mapping names to port numbers, but at least one daemon on your system uses service names instead of numbers. The daemon is inetd and it is that daemon that handles services such as chargen and echo and such. If you comment names out of /etc/services inetd gets confused and doesn't initialize the commented services. Effectively you did disable open ports. This is not an "unofficial" way of closing ports. This will work only with services managed by inetd and maybe for some other strange daemon that uses service names. It will not work even for inetd if it is configured properly. Effectively you are not stopping services. Instead you are confusing the hell out of your system forcing particular services crash on startup. It is the same as if you used winnuke to reboot your windows system. Works, but is not a good administration technique. From your initial mail I can point out that portmap, https, https, mysql etc cannot be stopped this way. As for the inetd managed services you should comment stuff out of inetd.conf or better disable inetd altogether.
