$700 Gaming Build - Newbie needs advice

I have never built a computer before and this will be my first one  

APPROXIMATE PURCHASE DATE: This Week

BUDGET RANGE: $700 Before Rebates

SYSTEM USAGE FROM MOST TO LEAST IMPORTANT: Gaming and programming

PARTS NOT REQUIRED: I need everything

PREFERRED WEBSITE(S) FOR PARTS: newegg

COUNTRY OF ORIGIN: USA

PARTS PREFERENCES: AMD CPU

OVERCLOCKING: Maybe

SLI OR CROSSFIRE: No

MONITOR RESOLUTION: > 1600x1200

ADDITIONAL COMMENTS:

1) Should a noobie overclock?
2) I plan to unlock 2 cores from the phenom to get quad core. Can I unlock with the mobo I chose?
3) Do I need a bigger power supply?
4) Can I survive with just the heatsink that comes with the cpu?
5) Keep in mind I still have to buy a monitor(I'm willing to go anywhere < $800 with a monitor)


Parts I have selected

Case:
COOLER MASTER RC-690-KKN1-GP Black SECC/ ABS ATX Mid Tower Computer Case
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

HD:
Western Digital AV-GP WD10EVDS 1TB SATA 3.0Gb/s 3.5" Internal AV Hard Drive -Bare Drive
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

MOBO:
MSI 770-G45 AM3 AMD 770 ATX AMD Motherboard
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Video Card:
EVGA 512-P3-N871-AR GeForce 9800 GTX+ 512MB 256-bit DDR3 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Power Supply:
Antec NEO ECO 520C 520W Continuous Power ATX12V v2.3 / EPS12V 80 PLUS Certified Active PFC Power Supply
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Memory:
G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9D-4GBRL
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

CPU:
AMD Phenom II X2 550 Callisto 3.1GHz Socket AM3 80W Dual-Core Desktop Processor HDX550WFGMBOX
http://www.newegg.com/Product/Product.aspx?Item=N82E168...


Comes out to $767 with a $130 monitor