Your first question "server placed in school LAN, access from LAN as well as from home":
The idea makes sense, and it is also the case in many schools.
Of course one needs a little bit of understanding about networking to do this. Here is a short description:
A school LAN is, as the name implies, "local". IE
, the computers get "private" internet addresses (IP addresses) which are not visible from outside. But you want your web-server (Moodle runs on a web-server) to be visible!
The solution is to ask your internet service provider (ISP) to assign you some public IP addresses. They are given in blocks of 4, 8 or more.
Once you get those addresses you assign your web-server one of them _in addition_ to the private address. Of course the domain
name system (DNS) and network routing should be adjusted, so that a common URL
always points to your web-server.
For the URL you have various alternatives: http://moodle.myschool.ac.uk
, etc. [Now for the impationt: Don't klick, the links are bogus!]
If you don't have the technical personnel, try recruiting somebody from your local community. You may even find a capable pupil. And if the server runs on free software you'll find the community helpfull. (That is exactly what happend in my son's school! ).
Your second question on "stats":
I was refering to the _present_ traffic, to get an idea what remains from the bandwidth. The most popular tool for that is called MRTG, a Swiss product. Here it is being used in my former working place 
P.S. We are drifting from the main topic of this forum. I suggest moving further discussion to http://moodle.org/mod/forum/view.php?id=50
or to a suitable newsgroup.