Setup my network

I have a mac mini, iPhone, and Airport Express... I also have a ps3 i go online with and another router (linksys wrt120n). now I want to set this up so that I can toggle with my mac mini between my airport express and my other router. i want my ps3 on that other router too . so i tried Modem, ethernet to Router (linksys wrt120n), ethernet to Airport Express (from the primary 1, of 1,2,3,4), and i got the orange blinking light but was able to go online. while doing that i was online with my ps3 wireless on the Router (linksys wrt120n). i was doing this because i wanted to be able to switch between the two UDP flooding the Router from my mac mini. I heard that I can use ozone on my iPhone or Net tools .. I am way out of my league here but I have the equipment and can get more if I need to . now I am a noob and I can get more Hardware if I need to i.e. switches, firewall's (jupiter netscreen etc..), whatever I need reasonably. also I am running Little Snitch. this keeps showing me that certain apps on my mac try to access ff02::fb..what is this? mDNSresponder is the culprit. is this guy cool ..? what about Bonjour? how should i have Bonjour setup in my Airport Utility ..? I need to go to the next level ya'll ...!1 somebody get me the **** out of the stone age..!! do I need to be concerned about my .local as well.? Little Snitch is showing me that my .local of my iPhone.local is being accessed by my computer wirelessly ? and also my macmini.local as well .. why is my .local folders being randomly accessed by my mac mini..? i need some real time chat help with someone who has some time for me .. i am on like 24/7 now so holler at me ..!!! Thank You Mac Heads ..;P uh by the way if anyone wants to talk to me about ircle and how to get going on that i have that too and am waiting for someone to show me how it works .. so get up with me and someone who has ircle too holler at me .. thank you