1. As far as security goes, make sure port 80 on your router directs traffic to your web server. If your webserver is running 10.2, the built-in firewall will protect unused ports. This does not mean that you are entirely safe since there's almost always going to be some vulnerability somewhere. You will, however, have blocked all of the easiest and most obvious points of entry.
2. As far as text-based configurations go, Apache's is clear and well-documented. Use the documentation on the Apache website (
http://httpd.apache.org/docs/) and a text editor (either something on the command line like emacs or something graphical like BBEdit) to explore your config file to at least familiarize yourself with it. I found this graphical frontend for Apache on Google:
http://www.webmin.com. There's also something called Comanche but its server was down...
3. How busy will your server be? My little server running off of my iBook (my main computer) generated a 2.9 megabyte log file in the past year. Most of this is garbage from Microsoft IIS machines infected with various worms trying to infect new IIS machines....
4. Check out WebMonkey (
http://hotwired.lycos.com/webmonkey/...ssi/index.html).
5. If your site gets a light amount of traffic as I imagine it would and your server is a newish Mac (past 2-3 years...it has to be if it's running X...), you won't notice serving slowing your daily usage/web browsing/etc. You could always turn web sharing on and off in System Preferences>Sharing>Services., though I doubt it's really necessary.
6. Apache doesn't use bandwidth unless it's sending something to a site visitor. I would make sure your router configuration is in order. It might also just have been a bad day for your ISP...
Peter
[Edit: I realized I gave a bad link to a commercial product in #2. Now it's a good link to a free product...]