I think you will find what I have to say....Well.... VERY EXCITING. First I want to tell you that you aren't in over your head. I am only 19 and I make my web server work over a dialup connection. Yup, that's right, good ole 56k, well not even that fast. Your cable will be more than enought to handle low traffic sites. There are a few things you will need and I'll give you all the help I can. (All software I am about to mention is free) Added bonus!!!
1.) You will need server software. Yeah Yeah yeah, I know. Oh my god... SERVER SOFTWARE!!!! It's not as complicated as it sounds. There are two That I can recomend for someone that is just playing around.
a. AnalogX Simple Server.
This is a really simple and good server to start with. to download it go to www.analogx.com There are directions to help you out.
b. Sambar Server.
Now this one is a little more complicated but it works great. It is the one that I use and took about 4 hours to set it up.
Both of these as well as a ton of other servers and tools can be downloaded from www.moochers.com click on the internet category and then Server Daemons and Tools. There are alot of great things to play with here. Have fun and try them. Playing with this stuff is how I learned.
2.) So now you have a server. Now I'm gonna help you get around having to type in the IP address to get to it. There is a really easy and simple solution to this and it is one that I wasn't aware of until yesterday actually. I have been using it for oh.... a total of 24 hours now and it is awesome. It is called DNS2Go. This thing kicks #####. You set up a program on you computer that sends your IP to a dns server. Here it is given a name wich you can customize. mine for example is www.dzone.d2g.com I know, it's not www.dzone.com but ya know what, it's not 30 characters long and it is free so I'm not complaining. To get this program go to http://www.dns2go.com and download it. It took me 15 minutes to setup.
Now I see you want to host a few websites. Since you only have one IP address, you can't access each site individually. Here is a simple solution for now. When you setup your server software, you will tell it what directory to find the html files in. The defauls is index.html (I don't know how much you know about this stuff so I'll pretend you don't know.) when someone is directed to your server it will load this default page. What I would do is make links to each of your other sites from this page. Then users are directed to the desired site. You'll figure all this junk out when you start playing with it.
There ya go. I think that after downloading analogx and DNS2Go it should take you no more than an hour to set it all up. If you have any other questions feel free to ask me. email@example.com and if you do get your sited up, send me the url so I can check it out.
Good luck and most importantly HAVE FUN!!!!
Take it easy