First Build - Advice greatly appreciated

This will be my very first build. I've been gaming for far too long with subpar systems and I decided it's time to build my own system. My budget is going to be around $1300 max. Since this is my first time building a system from the ground up, I just want to make sure I have everything I will need for the system to work properly. If there is anything that I have missed or compatibility issues please let me know. I do plan on making a slight attempt to overclock in the future once I'm a little more confident and have reasearched more, however, I don't plan on going SLI. ( That's for running two graphic cards if i'm not mistaken?)

When using the Antec Nine Hundred case, do I need to consider if the power cable from my PSU is long enough to connect to the mobo, since the Nine Hundred holds the PSU at the bottom?

I've only been able to locate OEM Hard drives, will I run into any complications with this seeing how it doesn't incude the wiring/manual and disk? If so, what will I need to purchase to complete the installation?

Also, I am really unclear on the OEM version of the Windows XP Home OS. From what I understand, you can only download this version once, if you try to upgrade/swap out your MOBO then you won't be able to use this copy. What if I have a faulty MOBO and have to order a new one, will I have to purchase another copy of Windows XP Home afterwards. How exactly does that work if someone could please enlighten me. As far as the OEM version, will it even be a good idea for a first time builder to use OEM or should I opt for the retail version. I would really like to avoid that if at all possible, the retail version puts me way over budget.

Here is what I am considering so far after alot of research. Thanks for any help in advance.

CASE:
Antec Nine Hundred Black Steel ATX Mid Tower Computer Case
http://www.newegg.com/Product/Prod [...] 6811129021
$119.00 - $40 mail in rebate = $79.99

PSU:
Corsair VX 550W Power Supply - CMPSU-550VX
http://www.buy.com/prod/Corsair-VX [...] 52646.html
$83.04 - $15 mail in rebate = 68.04

CPU:
Intel Core 2 Quad Q6600 Kentsfield 2.4GHz 2 x 4MB L2 Cache LGA 775 Quad-Core Processor - Retail
http://www.newegg.com/Product/Prod [...] 6819115017
$279.99

MOTHERBOARD:
GIGABYTE GA-P35-DS3L LGA 775 Intel P35 ATX Intel Motherboard - Retail
http://www.newegg.com/Product/Prod [...] 6813128059
$99.00

Cooling/Heatsink:
ARCTIC COOLING Freezer 7 Pro 92mm CPU Cooler - Retail
http://www.newegg.com/Product/Prod [...] 6835186134
$21.99

MEMORY:
CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory - Retail
http://www.newegg.com/Product/Prod [...] bXMS%2bRAM
$87.00 - $40.00 Mail In Rebate = $47.00

VIDEO CARD:
XFX PVT88PYDF4 GeForce 8800GT 512MB 256-bit GDDR3 PCI Express 2.0 HDCP Ready SLI Supported Video Card -
http://www.newegg.com/Product/Prod [...] 6814150252
$269.99

HARD DRIVE:
Western Digital Caviar SE WD5000AAJS 500GB 7200 RPM 8MB Cache SATA 3.0Gb/s Hard Drive - OEM
http://www.newegg.com/Product/Prod [...] 6822136178
$94.99

Optical Drive:
LITE-ON Black 20X DVD+R 8X DVD+RW 8X DVD+R DL 20X DVD-R 6X DVD-RW 12X DVD-RAM 16X DVD-ROM 48X CD-R 32X CD-RW 48X CD-ROM 2MB Cache SATA DVD Burner - Retail
http://www.newegg.com/Product/Prod [...] 6827106057
$34.99

OS:
Microsoft Windows XP Home With SP2B 1 Pack - OEM
http://www.newegg.com/Product/Prod [...] 6832116056
$89.99

Sound card:
Going to pick one up later

$1177.00 before shipping charges tallied
$1082.00 after rebates

Nice, except for that butt-ugly case. And you might want to get 2x 160/250GB drives with 16MB caches instead - JBOD RAID.

Thanks for the suggestions so far everyone. I'll definitely look for a retail version of the Windows-xp OS. I had a bad feeling about that OEM version to begin with thanks for clarifying that a_dude.

nhobo, I don't think the case looks too bad personally, it has kind of grown on me and the pros seem to outweigh the looks. Unless of course you know of a prettier box with similar/great air flow, I'm definitely open to any suggestions. You'll have to forgive my ignorance but what would be the benefit of switching over to the 2x 160/250GB drives with 16MB caches - JBOD RAID? My knowledge is limited so far but I'm learning. Would I need to switch out the mobo to something capable of utilizing RAID like the one aevm mentioned? I honestly have no idea if the current one does. (I'm going to research more on that).

aevm, great suggestions, I dropped the DVD-ROM and the Rosewill PCI card, definitely helps with the overall cost since I need to look into a retail OS. I'm currently reading up on that GA-P35-DS3R motherboard you mentioned (possibly more questions concerning that to follow). That is a decent price on the 22" monitor. Although, I may have to wait for the new monitor, depending on the final build cost w/shipping.

JBOD = Just a Bunch Of Drives. Put you OS/applications on one and your data and Windoze paging file on the other. Almost as fast at RAID0 without any of the drawbacks. More drives = more speed, just don't RAID them. I like the Gigabyte Triton case, clean & simple look, lots of features, quiet, great cooling, less cost.