I need to know if these parts are compatible

Yes they are compatible and the 750w Corsair power supply is more then you need for that system, any decent 500-550w would be fine for a none SLI motherboard and that graphic card. This 500w PC Power and Cooling would be fine and save you $40
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

I can see they are all from Newegg. Now if only I had the patience to click the links...

+1 to aevm for sharing my same sense of apathy

*wonders what the parts are*

here are the parts

APEVIA X-SNIPER G-Type X-SNIPERG-BL Black / Blue SECC Steel ATX Mid Tower Computer Case - Retail

Western Digital Caviar Black WD5001AALS 500GB 7200 RPM 32MB Cache SATA 3.0Gb/s Hard Drive - OEM

EVGA 01G-P3-N880-AR GeForce 9800 GTX+ 1GB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Retail

LITE-ON Black 18X DVD-ROM 48X CD-ROM SATA DVD-ROM Drive Model iHDS118-04 - OEM

PC Power & Cooling Silencer PPCS500 500W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Active PFC Power Supply - Retail

CORSAIR 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory - Retail

GIGABYTE GA-EP43-DS3L LGA 775 Intel P43 ATX Intel Motherboard - Retail

Intel Core 2 Quad Q8300 2.5GHz 4MB L2 Cache LGA 775 95W Quad-Core Processor - Retail

actually changed the case to:

RAIDMAX SAGITTA 2 ATX-928WS Black/ Silver 0.7mm SECC Steel ATX Mid Tower Removable MB Computer Case - Retail

Found out each second case is not so good so back to the first one

You might want to reconsider on the 9800+ and think about a radeon. they seem to be the sweet spot on bang for the buck and IMHO the 9800 is a little pricey for what you get in comparison

Change the mobo to GA-EP45-UD3R & GPU to HD4850.

is that HD4850 equivalent to the 9800+?

which brand of the HD4850

The same $70 buys you a bigger case (RC-690) with better cooling and without the crazy ugly lights. (Oops, did you LIKE the lights?)
http://www.newegg.com/Product/Product.aspx?Item=N82E16811119137

Techwizard is right. For example this HD 4850 1GB is $152 (as opposed to $190 for the 9800GTX+) and it's faster too.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814102802

Good HDD. The burner seems OK.

The Corsair 750TX is overkill since the DS3L won't allow SLI or Crossfire. The Silencer 500W will do very nicely there.

I have some doubts about that Q8300. An E8500 costs $2 less, has only 2 cores instead of 4, runs at 3.16 GHz instead of 2.5 GHz. If the PC will be used mostly for games, and you don't play FSX or GTA4, then the E8500 will serve you better. If the PC is used mostly for FSX, GTA4, video encoding, Photoshop, database work and other quad-friendly things then the Q8300 is the better choice between these two. Try to figure out which one makes more sense for you, OK?

MSI for $125AR, or ASUS for $135AR including free WOW.

There's also the Antec 300, BTW. $65 with free shipping, not bad at all.
http://www.newegg.com/Product/Product.aspx?Item=N82E16811129042&Tpk=Antec%20300

@theAnimal

If I were the OP and had to choose between the two, $10 to lose MSI for ASUS seems a pretty safe bet.

okay changed the parts requested now here are the parts just to check to make sure i have everything and that itll all fit and work:

case: cooler master RC-690-KKn1-GP

mobo: GIGABYTE GA-EP45-UD3R LGA 775 Intel P45 ATX Intel Motherboard

CPU: Intel Core 2 Quad Q6600 Kentsfield 2.4GHz LGA 775 Quad-Core Processor Model

video card: SAPPHIRE 100258-1GL Radeon HD 4850 1GB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card

RAM: CORSAIR 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel

PSU: CORSAIR CMPSU-750TX 750W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Active PFC Compatible with Core i7 Power Supply
(This is more than I need, but I don't want to have to buy another one when i upgrade this rig)

HDD: WD 500g 7200rpm sata

Disk Drive: 18x liteon r/rw dvd

heat sink: COOLER MASTER GeminII S RR-CCH-PBU1-GP 120mm Sleeve CPU Cooler

is this all ill need? and if so will it fit together?

change the HDD to the WD 640--the platter size makes the speed increase quite noticeable

maybe consider mushkin of g.skill on the ram--the pi black is hugely popular 'round deese parts

I would choose Q8300 over Q6600, it's faster & cooler.

For a single video card system, 750W is overkill. Corsair VX550 or PC P&C Silencer 500W would be good.

Yeah, how did the downgrade from 83 to 66 occur? It's like someone stripped us of computing power for no reason =(

alright i put the 8300 on and downgraded to a 650w psu

Which 650W PSU? The Corsair 650TX is very good.

Do you think you'll want Crossfire? All you'd need to support that is spend a few bucks more and get the GA-EP45-UD3P instead of GA-EP45-UD3R.