pre-buying anxiety!!! :(

Ive been reading around on these forums alot, and ive finally gone and chosen the parts i want for my computer. This is my first time building, so im hoping that its not too hard, and that i wont seriously mess something up. Here it is.

Motherboard: ABIT IS7,Intel 865PE chipset for Socket 478 P4 ATX motherboard RETAIL
Processor: Intel Pentium 4 / 2.8CGHz 512k socket 478 Hyper Threading Technology 800 MHz FSB - RETAIL
Case: CHIEFTEC Server Chasis (Aluminum Workstation Tower with Plastic Front Cover) BLACK w/450Watt Foxconn Power Supply & acrylic window **Now with 2 x Front USB2.0 and 1 x Firewire IEEE1394 ports**
RAM: KINGSTON HyperX Series 184-pin 1GB Kit (2x 512MB) DDR433 (PC3500) DDR RAM modules, Model# KHX3500K2/1G
HD: Seagate 120GB 7200rpm SATA Hard Drive Barracuda 7200.7 ST3120026AS - OEM
CD-RW: Lite On 52x32x52x Black Color CDRW Drive LTR-52327S - OEM
DVD-ROM: LITE-ON XJ-HD166/XJ-HD 165H 16X DVD ROM Drive BLACK- OEM48X CD-ROM
Speakers: Logitech Z640 5.1 Speaker – RETAIL
Video Card: POWERCOLOR ATI RADEON 9800 128MB DDR DVI/TV-out 8X AGP (Non Pro) RETAIL
Keyboard+ Mouse: Chieftec Wireless Keyboard and OPTICAL Mouse Combo, PS2 Retail


So, how is it?? I need EVERYTHING but a monitor, so am i missing anything small that i forgot to get?? like some cables and fans or something?? Im getting the processor retail, do i need to get thermal paste or something like that. How is the powersupply on the case im getting?? Im not too tight on cash, but i there is anything i could cut off that wouldnt really mess up performance please point it out . Otherwise basically how is the setup, ANY help would be appreciated, or if it looks good, some reassurance that im not making a bad choice in deciding to build this computer myself.

Still feeling like a might be making a mistake, how is the building part of it? IS building a computer pretty easy, ive never actually messed around inside a computer, but maybe theres a guide or something i can follow. I just dont want to get all the parts and have no clue what to do with them.

Someone told me the Foxconn 450W power supply was crappy, so could any of you guys recomend a case and good, quiet (doesnt have to be perfectly quiet, just not loud) power supply for about 150$? thanks

problem is, its too expensive , i need a case + PSU for 150$....hmmm i might get the Sonata, the Antec 380 True PSU, that comes with that- enough to power my computer right????

Hey guys, now that i got the case and PSU picked out, somebody says that the HyperX RAM, might be a problem with my IS7 board, is this true( or not true) ?. Does anybody have HyperX RAM and an IS7 board that can confirm this problem, or prove it wrong??

THanks

You asked how easy it was to build your first computer? I just did! and except for the wiring from the power supply (I made it too confusing) I did ok. NO problems! I have a ABit IS7, P4 2.8 800, and 2 512's of Cosair 3500 Extreme memory. You asked about Kingston memory, I went with Cosair as I didn't want any problems. (read about others with kingston and some minor problems) Went with ABit as least problems. Yes, it was costly, but this system is really fast. I just got it up and running this am. If you have a question, I can try and answer as I just built it and its still Um, fresh in my memory! I also bought a chieftec blue case.

http://www6.tomshardware.com/howto/index.html

get a howto in building a pc there if you are still a bit clueless on how to get a pc up and running...