1) Cygwin has inetd, and you could configure that to launch your code. Once you get the Cygwin base install could also use Cygwin perl/php/python, even bash to be a net daemon.
2) you could run any of these under apache, which is the most common way of running net code for most of these scripts. You'd have to be ok with wrapping your data in HTTP, but it also gives you a lot, including config, process management, logging, etc.
3) Any of these scripting languages can create a listen socket and serve code that way. You could use any scheduler to start the script to be a daemon on it's own.
Any particular reason why you're trying inetd and not run under apache?
The inetd model was for infrequent, long run connections like telnet. If that's your model, then fine. But if it's many short run connections, apache may be a better controller for you.