New at building a computer

So I'm looking at building a new pc and it's my first time at it. I'm pretty sure I have everything I need but I just want to make sure I've got the right stuff for the new build. 

I'm looking at buying:

-GTX 260 896mb (newegg $215)

-Artic Cooling Freezer 7 Pro 92mm CPU Cooler (newegg $26)

 Then from CompUSA I found a barebone kit for $349 that includes:

-XFX MG-63MI-7109MoBo

-Corsair 4gb DDR2 ram

-Utra-X-Blaster ATX mid-tower case

-Power Up 550 watt PSU

-Intel quad core 6700 2.66 Ghz OEM

Is this all I need to build a new computer or am I missing something? I'll be using my hard drive from my last computer so I won't be needing a new one. Also, I read about using thermal grease when installing a processor. What's that all about?

~Thanks

Ok so I took your advice and decided to go with the following:

Cool Master NV 690 Case

Intel Quad Core Q6600 @ 2.4ghz 

Rosewill RP550 watt PSU

Gigabyte GA-EP45-UD3R LGA 775 Intel ATX MoBo

Artic Cooling Freezer 7 Pro 92mm CPU Cooler/Heatsink

GTX 260 896mb Video Card

 I'm still not sure about the motherboard though, any comments?

Ok so I took your advice and decided to go with the following:

Cool Master NV 690 Case

Intel Quad Core Q6600 @ 2.4ghz 

Rosewill RP550 watt PSU

Gigabyte GA-EP45-UD3R LGA 775 Intel ATX MoBo

Artic Cooling Freezer 7 Pro 92mm CPU Cooler/Heatsink

GTX 260 896mb Video Card

 I'm still not sure about the motherboard though, any comments?

Silly5

Thanks a lot for teh response! My question with the e8400 is that yeah it's 3ghz but it's still only dual core. How is that better than a quad? Also, will I need thermal grease or w/e to install the CPU?

thanks