I will second Kimmo's recommendation for the Antec P180B case. NewEgg is offering a $30 rebate this week (it was $50 last week), and if you use PayPal, you can save an additional $10 with the coupon code PAYPAL10. For your needs, the P180B should more than suffice (I think a full tower is overkill): it has 6 3.5" drive bays (i.e. you can hold 6 HDDs) and it has sound-deadening panels (which you'll need for a HTPC-type setup; you want to suppress as much noise as you can). Having just ordered one myself, I can safely say that it's slightly taller than the CM Centurion 534 (which I also ordered), but the internal layout is superior. Also, if you order a P180B now, chances are you're likely to receive a P182 instead (the successor is even better, as it includes external fan control for the top and rear fans and rubber ports, which are handy for those desiring a watercooled solution; here is the product info page)
Even if you do decide to go with an SLI/Crossfire setup, I think a mid-tower ATX case will work just fine. A typical mid-tower should have enough 3.5" drive bays to house at least 4-5 HDDs. If you decide to go with a mid-tower (and based on your wishlist, I do believe it's all you really need), you may want to consider one of the Centurions from CM (Cooler Master). I ordered a Centurion 534 w/ side window for $29.99 from SVC (S&H was ~$21, IIRC) to replace my aging beige mid-tower ATX case; they also have a 531 w/o a window for $5 more; either of these Centurions will suit your needs very well.
If this PC is going to be used as an HTPC, you may want quieter components, particularly the PSU and additional 120mm case fans. Taking into account budgetary considerations, I would likely forego the full tower case for one of the Centurions and use the money towards a better-rated and quieter PSU (the Antec NeoPower NeoHE 550W would be an excellent choice here, as it supports SATA, PCI-E, dual video cards, and dual CPUs, has a high efficiency rating and is significantly quieter than most others with this power rating).
As for heatsinks, you may want to consider one that will support a 120mm fan, as it's more likely to push higher CFMs with lower noise (whether or not the fan is undervolted). Lots of solid choices here: the Thermalright Ultra 120 or 120 eXtreme, Scythe Ninja Plus Rev. B, Tuniq Tower, OCZ Vindicator, Enzotech Ultra-X, to name a few. A couple of these can even be cooled passively, even with the CPU slightly overclocked (although it's safer to have a fan attached and have it undervolted to 5V or 7V). You will need to spend a bit more (about $15-20 more than the Thermaltake HSF on your wishlist), but these will allow you to push your CPU a bit farther without the accompanying increase in noise level.
If you're looking to stay around the $100 range for video cards, an X1650PRO or X1650XT will offer better performance (and IMHO, image quality) than a similarly-priced 7600GS. HIS Hightech and Sapphire are both exceptional ATI third-party manufacturers; as long as you're not upgrading to Vista anytime soon , the Catalyst driver on XP is rock solid.
Intel will be dropping prices on their current Core 2 Duo processors on or around April 22 to coincide with the launch of three new C2D CPUs (E6420, E6320 & E4400). AMD's price cuts were announced yesterday (link). Some food for thought before you place your order.
You have almost unlimited options for cases priced $80 or less, if you're willing to consider a mid-tower. Personally, I don't know any PC gamers like myself who own a full tower case. You can get a Cooler Master Centurion case (including S&H) for ~$50, and you can use the $30 you saved towards another component / peripheral.
I am pretty much DONE waiting. My brothers are annoying the heck out of me, and I got to get them out of my room. This is the best way to be able to have my room back, AND to have some great fun with it!
Thanks for all of your guys help!!
P.S. I'm NEVER going to get AMD... All of the computers I had had AMD processors, I was unhappy with all of them. And, AMD just doesn't stand up to the C2Duo's. Almost no competition performance-wise.
After a bit more research, I think the Antec PSU in your wishlist should be fine. It's not SLI or Crossfire certified, but seeing as your mobo doesn't support either anyway, it's not really a concern.
If your budget permits, an extra gig of memory (as Dennis suggested) would be a worthwhile investment (if you're a gamer, you'll definitely notice the difference in performance). Again, it's not compulsory, but nice to have (I'm using 1GB myself); otherwise, I think you're set.
Nothing against NewEgg (I'm a regular shopper there as well), but there are other reputable e-tailers with prices, selection and service every bit as good, if not better than the Egg. I understand the convenience of doing shopping at one outlet; just don't overlook its competitors.
I prefer to get them all at one place, to save some money (S&H), and to get it all at the same time. I would only get parts somewhere else if they had a large difference in price, even with S&H. If I buy from newegg, it charges me $30, for all of the order. So, I don't have to pay S&H for 20 items (each) when I can just pay $30 and be done with it. I'll upgrade the memory to 4GB after I get my Dayton 8's, Dayton III, and DVC subwoofer finished. Then, I'll have a great system to hook this great system up to!
All depends on the application, I have 25 webservers, all the AMD X2's run circles around anything, and I mean anything Intel has out, including my Xeon, the dual Opteron makes Intel look like it is still in the stone age.
If you have any questions about parts you are about to order or parts you might order instead, just ask away. I just put together this system.
Antec Nine Hundred case OCZ OCZ600GXSSLI GameXStream 600W Power Supply Intel E6600 CPU Gigabyte P965-DS3 OCZ 2GB Platinum Rev. 2 Western Digital 320GB SATA Lite-On 20X Dual Layer DVD+/-RW Drive Tuniq Tower 120 Windows Vista Already had 7600GS (not great but good enough for my fiance' to play Sims2)