Want to setup home LAN

Maybe it should be considered a HAN rather than a LAN, but either way, I would like to setup a network in which all of my computers in the house can access the other and transfer files if needed, or backup to my soon-to-be data server. Here's the lineup of what is/will be connected during this summer:

Wireless:
MacBook Pro
Dell Latitude D630
Dell Latitude 420
Dell Inspiron 5100

Wired:
Dell Precision T3400
Dell Dimension E310
PowerMac G5 1
PowerMac G5 (data server)

So far, the above is my setup at home, i tried this at my apartment at school with my MBP and Precision, is this is where i am now:

So my Windows computer sees my MacBook Pro no problem, though it only will connect if i let it use my user account on the Mac, it won't connect as an anonymous user. I just can't get the Mac to fully connect to the Dell though, it does see it, but returns connection failed when i try to.

Any help would be appreciated, thanks

Here is one:

1. Install the latest version of Internet Explorer that allows
drag-n-drop FTP. I know both five and six do--I suspect the
new ones do as well. Turn on that feature. For background,
see
<http://freepages.computers.rootsweb.ancestry.com/~pasher/dragndrop.htm>
or <http://tinyurl.com/3krw7er>
(an OLD page but I doubt the basics have changed.)
IIRC, the feature is "enable folder view for FTP sites"

2. Enable FTP on the Mac

3. Open IE, point it to ftp://userid(E-Mail Removed) where
- w.x.y.z is the IP address of the Mac which you can determine
by looking in network preferences (or ifconfig in shell)
- userid is the account that has the files in its home directory

4. Start dragging things from IE's simulated directory window to
a "real" Windows directory. Drag whole folders if you wish,
or select a whole bunch with the mouse _exactly_ the way you
do local files and drag all at once. Copy/Paste and even
Cut/Paste also works.

Others may not think so, but to me, doing this is WAY easier than
describing it.

To make it go a little faster, use Cat-5 through a router or switch
instead of WiFi. Would probably even work with a direct connection
if you have a CROSSOVER cable. A web search or your favorite geek
can tell you what's the difference.

Thanks for your response, but i think you might not fully understand what i'm trying to do. At this present time, i can send files to my Mac and take files from it through Windows no problem, but I cannot do the same from the Mac itself. So i'm trying to figure out why, because using smb or ftp both return server not found or could not connect. At the moment, everything is over ethernet to a router, I am not using wireless at this time, eventually i will, but not now. Also, even though a crossover cable might be a good idea, I might as well just scrap the whole idea of making a HAN and use a flash drive to transfer files, using a crossover cable isn't really an option.

What are your DNS servers pointing to on the Mac? Is the DNS Server on the Router and DHCP handing out those addresses for the machines to use? What happens if you try to connect via IP rather than name?

You know what, I think i figured it out. It turned out that my firewall, Little Snitch, was blocking some service which allowed for that access to the LAN. I was just going through all my rules and deleting each one to see fi it changed the error, and one of the last ones did the job, though i really don't remember what its name was. But all is good now, so thanks for your help!