[New System Build] Light Gaming, Multitasking ~$700 budget

APPROXIMATE PURCHASE DATE: ASAP, hopefully by Friday.

BUDGET RANGE: 700, i would say $725 would be a very strict max

SYSTEM USAGE FROM MOST TO LEAST IMPORTANT: Light gaming (wc3/sc2), usually likes to have a lot of programs running (like music, video, browser, game, vent, skype, and a few other things at the same time.

PARTS NOT REQUIRED: OS, Monitor, Keyboard, Mouse

PREFERRED WEBSITE(S) FOR PARTS: newegg.com
COUNTRY: USA (Virginia)

PARTS PREFERENCES: no parts preference BUT NEEDS A WIRELESS CARD (Preferably N)

OVERCLOCKING: No (or very very little)
SLI OR CROSSFIRE: No

MONITOR RESOLUTION: 1920x1080 + second monitor (cheap one, i think something like 1024x768)

ADDITIONAL COMMENTS: This is actually for a friend, I very recently built my own computer that I am using as sort of a blueprint, I was wondering what should be upgraded from this package (which is almost exactly 650 when I bought it):

Rosewill RNX-N300 IEEE 802.11b/g/n Wireless-N 2.0 PCI (1T2R) Up to 150Mbps Data Rates/ WPA/WPA2 (AES, 64,128-WEP with shared-key authentication) Cisco CCS V1.0, V2.0 and V3.0 compliant/ Vista Ready - Retail

LG Black 22X DVD+R 8X DVD+RW 22X DVD-R 6X DVD-RW 12X DVD-RAM 16X DVD-ROM 48X CD-R 32X CD-RW 48X CD-ROM 2MB Cache SATA 22X DVD Burner - Bulk LightScribe Support - OEM

Seagate Barracuda 7200.12 ST3500418AS 500GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive

G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9D-4GBRL - Retail

AMD Athlon II X4 620 Propus 2.6GHz 4 x 512KB L2 Cache Socket AM3 95W Quad-Core Processor - Retail

Antec earthwatts EA500 500W Continuous Power ATX12V v2.2 80 PLUS Certified Active PFC "Compatible with Core i7/Core i5" Power Supply - Retail

SAPPHIRE 100283-3L Radeon HD 5770 1GB 128-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card - Retail

ASUS M4A785TD-V EVO AM3 AMD 785G HDMI ATX AMD Motherboard - Retail

Antec Three Hundred Black Steel ATX Mid Tower Computer Case - Retail