opinion for narrowing down audio system?

So after reading through some forums, i've narrowed it down to an RE and US Amp setup. and just so you guys know what i looked through, i checked out Digital Designs, FI Car Audio, AudioQue, Resonant Engineering, Image Dynamics, and Ascendant Audio. Originally, my choice was MTX, but i suppose i can't really spend that kind of money right now, and according to a lot of experience people, i can get some good underground equipment thats almost as good.

So i'm thinking either 2 12" SE Dual 4 Ohm Subwoofers (600W RMS each), or 2 12" SX Dual 4 Ohm Subwoofers (1000W RMS each)

I would pair it up with a US Amp MD.1DN, which does 1200W RMS @ 1 Ohm, or a US Amp MD.3DN, which does 2000RMS @ 1 Ohm (respectively)

After deciding between those two setups, im going to be using a US Amp MD.42.N four channel amp either running Infinity Kappa speakers at 125 x 4 RMS @ 2 Ohms, or Infinity Kappa Perfects at 90 x 4 RMS @ 4 Ohms

I already have a less than a month old Optima Yellow Top under the hood. i'm not sure how big my current alternator is right now, but i know that even now, with only a 600W RMS amp and a 1 farad capacitor, i still get some lights dimming, so it can't be too powerful.

So first of all, what do you guys think as far as choosing the system components. and once that is decided, should i just get a higher output alternator, like i was thinking about ordering a 140A Tuff Stuff alternator from Summit,  and that would be enough? or should i also just add on a secondary battery, or i'll be ok just with the secondary battery. and if i use the battery, do i jus hook it up parallel with the front battery, or use a  relay or solenoid. I know theres a lot of controversey over that, so heres what u need to know (i think). i dont plan to have my sounds on too often with my vehicle off. i'm sure i will do it once in a while at a party or barbeqeu (it is summertime), but i would say at the most it would b on half hr to an hr at the most. i also read that if u just connect the two batts in parallel with no relay, that they will constant discharge each other when the car is off. However, i've seen a few people post that as long as u use the same batt (age/capacitance/etc), that wont happen. also, the other thing i worry about is that if i dont use a relay, what happens if my batts discharge and i cant start the car one day, am i gna b able to use a simple jump start, or what would happen. Sorry for typing so much, i just wanted to be thorough so i could get a thorough answer. thanks

ps - since i'm already on here asking questions. as i said before, im not trying to cheap out, but i wanna get good equipment, without spending so much, trying to shop smart. also, since i do work somewhere where they sell audio equipent, i can get some stuff like type r's and spkrs for very cheap, which i know are very good, but A LOT of people have that. i wanted to have something a lil bit diff from other ppl (around here anyway). so for the head unit, i was choosing between the Kenwood Excelon KVT-819DVD ($560), and the Clarion VRX-785BT ($440). they both have HPF, 3 pre outs, and ipod video and audio control, which are prob the most important to me. however, the kenwood has 5 volt preouts & DSP. also, in my car (1983 Oldsmobile Delta 88 Royale Brougham), the area where the stereo goes is a lil recessed, so the heater control knobs wil prob get in the way of most DVD players. so i would have to do a lil custom modification for the clarion, but like i said, it's something a lil different. the kenwood screen comes out really far and is very adjustable, so i think it should work fine. any opinions?

Those are all great products you are looking at from what I hear... except your alt. you're looking at pulling up to and over 225 amps!  Definitly buy the biggest alt you can afford.