back up

Since upgrading to back up i am being told my HP recovery is unable to complkete the back up i purchased a cd but this is the same What do I need to back up regularly
thankyou

What edition of Windows 7 are you running

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PC: home build (built and owned by an old git)
Case:Antec 300
PSU: CoolMaster Real Power M700
TFT Screen: ASUS VH226 21.7"
Mother Board;Asus P5Q DeLuxe
CPU: Intel Core 2 Quad Q8200 2.33GHz 1333FSB (Retail 775
RAM: GeIL Black Dragon 8GB (4x2GB) DDR2 PC2-8500C5 1066MHz Dual Channel Kit
O S:Microsoft 7 Ultimate 64 bit
Speakers: Logitech Z 5500
Sound Card: Auzen X-Meridian (Dam good it is to worth every penny)
Video Card: Saphire HD4870 Toxic 1GB
Hard Discs:
C: SAMSUNG: HD103UJ [Hard drive] (1000.20 GB)
D: SAMSUNG: HD103UJ [Hard drive] (1000.20 GB C drive raid
G: SAMSUNG: HD103UJ [Hard drive] (1000.20 GB