well, you can IM me on AIM, same as my name on here. Also, my email is firstname.lastname@example.org. Anyways, let me see if i can help you with a few questions on here.
You mentioned capacitors (cap) a lot in your questions. A capacitor basically goes on the power wire right before your amp and stores up power quickly in between the bass hits and the gives your amp the power when it needs it especially on the really loud and low hits. They arnt absolutly necessary, but can help your electrical system and can give your amp a little extra power on big bass hits. They come in different ratings of power, called farads. Generally, 1/2 farad is for amps up to 500 watts and 1 farad is for up to 1000 watts. Ummmmm... You mentioned a distribution block. That basically just takes a power wire and splits it into multiple wires and sometimes fuses them. Hmmmm, what else. YOu asked what 4 guage wiring is. The guage of a wire is the measure of its thickness. The smaller the number, the thicker the wire. As the wire gets bigger, then it can handle more power. Also, awg and guage basically mean the same thing. And, i will quickly answer some of your questions about what the abreviations meant. SPL stands for sound pressure level and is basically a measure of how loud your system is. Also, you didnt include this in your abreviations, but SQ means sound quality. Systems are usally described as either SQ or SPL or a balance between the both. SPL systems are made to be nothing but loud, and SQ systems are made to sound as good as possible with not as much regard to the volume of the system. I might be wrong, but i think that RMS stands for root mean squared. But, what it stands for really doesnt matter. It is basically the amount of power something can continuously give or take. OK, i guess that is enough for now. I couldnt answer everything, but it would take a lot more to thouroughly answer all those quesitons. It sounds like you just need to either get somebody to do your whole system for your or do lots of reading.
Check out my system at http://www.sounddomain.com/id/crzybob77