Internet Networking Question

I am not sure where to post this, as I cannot find a networking forum? Did I miss it? Anyway, I have a Dual Core 2.0Ghz MacPro and a few power PCs, soon to be upgraded to Intel machines. I want to set up a cable or DSL or modem connection. I recently remodeled and have Two Cat 5e and 1-2 Coax Cable drops going to multiple locations. The MacPro does not have a Airport card, so I was considering getting one, or just running it off of one of the hard wired connections. If I did this, what else would I need to make this work? I presume that most routers will send a hard wired signal to 4-6 locations. If I get a wireless router, my understanding is that I can do both 4-6 hard wired locations and a wireless signal throughout the house. I have all of my drops homerunned to a central telephone closet in the house. So if I terminate the corresponding cables in the closet with RJ11 plugs to plug into the router from the modem, what do I do at the other end? Do I have to terminate the wall plates with RJ45 plugs or can I have do it with a RJ11 plug? Then what do I do? Can I run a RJ11 terminated cable to the Ethernet port, or does that require RJ45? Can anyone help if you can! Also any recommendations for Cable vs. DSL would be appreciated. I am assuming with Cable, I merely terminated a coax run to modem and then RJ11 cables into the Router? Any recommendations for Modems and Routers would be appreciated. This is the first time that I have set up a network. I merely just ran the drops to all of the locations, waiting to plan my next step!