Please help me decide, host site myself or use a service

[Harry Wordsworth]

Hello good ranchers. I am hoping you can help me make a decision.

I am trying to choose between a) Hosting a web site on my own computer or b) using a java hosting service.

Background:

A few years ago I had a site up and used a java hosting service. They were ok, about $75 a year for my hosting plan and $14 for my domain name every year.

I've recently been looking into just hosting a site on my own home computer. I am thinking of the whole thing as a learning exercise to get to understand networks and the ins and outs of hosting a site.
This is where it gets a little more complicated and add in the fact I have no experience doing anything with networks. The site is easy to create but networks....

My ISP is timewarner cable.

I currently have 2 computers, lets call them "computer_old" and "computer_new"

"computer_new" is, as you would suspect, new but I don't want to host the website on it. Primarily because if someone "hacks" the site I don't want my main computer I use for everything to be hacked. I have security software on it however.
So I was thinking of getting a very cheap like less than $200 used laptop or pc to host the site on.

I was originally thinking of using "computer_old" but if it means connecting it to a network with "computer_new" then I'd rather not.
I've had "computer_old" for about 10 years before recently upgrading to "computer_new".
On "computer_old" I've had all sorts of virus infections over the years so I do not trust it to be on the same network as my main home computer unless I could ensure nothing bad from or going through "computer_old" could get to "computer_new".

So my options are
a1) - host a site on my "computer_old" somehow setting things up so it is on the same network as "computer_new" but can't get to it, maybe that trivially simple or hard, I have no idea.

a2) - host a site on a new cheap computer I can buy - also separate from "computer_new", which would be good but then again I am not sure how to set this up either

b) - just upload my already completed website to a hosting company

I know very little about networks and such so it's possible the way I have phrased the question does not make sense? if so please let me know.

[Ron McLeod]

If you goal is to understand networks and the ins and outs of hosting a site, then what better than to take on setting it all up yourself (of course this is dependent on your ISP allowing you to host a server on your home connection).

Regarding the computer, as long as the old one has enough RAM and disk storage, I would backup whatever you need from it and reloaded it with Linux + Tomcat/JBoss + MySQL/PostgreSQL.  You can run all those subsystems  with 2GB of RAM and 20GB of storage (of  course more RAM or storage wouldn’t hurt).  If necessary, buy a cheap router to segregate the server computer with its own network which cannot access any devices on your main home network.