My First Home Network

[kaos kid]

I'm ready to setup my first home network. My hardware is a Linksys BEFCMU10v3 Cable Modem and a WRT54GLv1.1 wireless router and I would like to have 3 boxes share an internet connection, with one box wired to port 1 and the other two for my kids connected with WUSB54G wireless USB2 adapters. After reading about flashing to the latest firmware (either Linksys or 3rd party) I'm thinking I would like to do that once I know what I'm doing but I think I should just get it up and running first before I take a chance on bricking the router.
Currently I am using a software firewall along with Protowall IP blocker. I have excluded the modem range in my blocklist so that is no longer an issue, but it appears that the software firewall is interfering with proper setup. After disabling the software firewall, setup seemed to work better, but there were still some things I don't understand. Where in Network Connections I normally see that I am connected and have a standard IP addy, during setup I only saw the 192.XXX.XXX.XXX addy in that connection, but then another connection icon named "Gateway" although its properties tab wouldn't give me an addy--I went to a site that told me what my IP was (this was only using the wired port, I am not hooking up the other wireless adapters until I get this one ironed out).
Do I need to even use the software firewall anymore, or should I disable for good? If I do need still need it, how do I make it play nice with the router setup? I am hesitant to proceed further without knowing for sure what I'm doing. The router only came with a CD for setup but I don't trust it without hardcopy instructions, FAQ's, etc. to refer to. Shoud I go ahead and try to setup again using the Linksys setup CD and firewall disabled? Thanks for your suggestions.

...edited for clarity

 

[JackMDS]

http://www.ezlan.net/firewall.html

 

[Markbnj]

I'm not familiar with that Linksys unit. Is it an access point/router as well as a cable modem?

The typical setup for a home network is internet<->cable modem<->ap/router<->client machine.

That pretty much takes care of people trying to probe into your network from outside. Then, as Jack's page points out, you need to consider whether you are likely to pick up something nasty from a site you visited voluntarily. If something like that gets onto a client machine then it can connect outbound through your router with no problems. That's where a software firewall on the client machine comes in. A good one will monitor and inform you if some software tries to initiate an outbound connection.

Whether you need that, or not, is a matter of whether you visit the kinds of sites that might delivery a stinky payload onto your client. If you have kids/teens at home, then the answer is a definite yes, and the machines they use should have a software firewall. I personally have firewalls running on my kids' machines, but not on mine or my wife's.