First Build Please Review

All parts from Newegg.com this will be my first build ever and I am trying to save money but still be able to play games and enjoy them for years to come without having to spend any money on uprgading my PC for a few years. Any suggestions are advice on the listed equipment would be greatly appreciated. Also I am wondering should I save up and buy everything at once or buy what I can a little bit over time until it's complete? I will not be looking to overclock or anything really technical due to inexperience I am also worried about putting it all together but from what I hear its all very simple everything just screws in naturally.

Optical Drive: ASUS DRW-24B1ST/BLK/B/AS Black SATA 24X DVD Burner - Bulk - OEM

Case: Rosewill CHALLENGER Black Gaming ATX Mid Tower Computer Case, comes with Three Fans-1x Front Blue LED 120mm Fan, 1x Top 140mm

HDD: Western Digital WD Black WD1002FAEX 1TB 7200 RPM SATA 6.0Gb/s 3.5" Internal Hard Drive -Bare Drive

GPU: PowerColor PCS+ AX7950 3GBD5-2DHPP Radeon HD 7950 3GB 384-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video

PSU: Rosewill CAPSTONE Series CAPSTONE-550-M 550W ATX12V v2.31 & EPS12V v2.92 SLI Ready CrossFire Ready 80 PLUS GOLD Certified

Memory: G.SKILL Ripjaws X Series 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800)

MOBO: ASRock Z77 Extreme4 LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard

CPU: Intel Core i5-3570K Ivy Bridge 3.4GHz (3.8GHz Turbo) LGA 1155 77W Quad-Core Desktop Processor Intel HD Graphics 4000

Subtotal: $1,039.92