Bargain Hunting for Windows 7?

Computer Type: PC/Desktop
System Manufacturer/Model Number: Intel(R) Core(TM) i5-2320 CPU @ 3.00GHz (Gateway computer)
OS: Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1
CPU: Intel(R) Core(TM) i5-2320 CPU @ 3.00GHz
Motherboard: Gateway IPISB-VR
Memory: 8.00 GB
Graphics Card: Intel(R) HD Graphics
Sound Card: (1) Realtek High Definition Audio (2) Intel(R) Display Aud
Monitor(s) Displays: ViewSonic 2250 Series
Screen Resolution: 1920 x 1080 x 32 bits (4294967296 colors) @ 60 Hz
Keyboard: Gateway
Mouse: Logitech
Hard Drives: (1) WDC WD10EADX-22TDHB0 (2) Generic Mini SD Reader USB Device (3) Generic USB CF Reader USB Device (4) Generic USB MS Reader USB Device (5) Generic USB SD Reader USB Device (6) Generic USB xD/SM Reader USB Device (7) Seagate FreeAgent Go
Internet Speed: 20 Mbps (Theoretical.)
Browser: Firefox
Antivirus: Avast

System Manufacturer/Model Number: HP Pavillion dv-7 1005 Tx
OS: Win 8 Release candidate 8400
CPU: 2@2.4
Memory: 4 gigs
Graphics Card: Nvidia 9600M
Sound Card: HD built-in
Monitor(s) Displays: 17" Wxga
Screen Resolution: 1440x900
Cooling: none
Internet Speed: 45Mb down 5Mb up

System Manufacturer/Model Number: Desktop
OS: Windows 7 Professional x64
CPU: Intel i5-2500k @ 3.3Ghz
Motherboard: Gigabyte GA-Z77X-UD5H
Memory: 4GB DDR3
Graphics Card: Nvidia GTS250 1GB
Monitor(s) Displays: Sony SDM S95A
Screen Resolution: 1280x1024
Keyboard: Logitech Media Keyboard
Mouse: Microsoft Intellimouse
PSU: Corsair HX850W
Case: Cooler Master 690 II
Cooling: Thermalright True Spirit 140mm & 3x 120mm & 3x 140mm Fans
Hard Drives: 1x 1TB, 2x 250GB HDDs
Internet Speed: 8MB