If you need to install or reinstall Windows 7 you can use this page to download a disc image (ISO file) to create your own installation media using either a USB flash drive or a DVD.
But You're Need Sometings Before begin
1. A Windows 7 product key (xxxxx-xxxxx-xxxxx-xxxxx-xxxxx).
The key numbers can be found on/under/behind/in front of the computer/laptop case, on the Windows DVD or on the user manuel books.
2. An internet connection and computer (For downloading data up to 2 GB.)
3. A blank USB or DVD (min 4 GB)
Where are the Windows 7 SP1 Latest Legal Version Download Link?
Download Windows 7 Disc Images (ISO Files) Download Link
You can click for download to adress from Microsoft Offical Webside:
How Can I download Offical Windows 7 SP1 Latest Version From Microsoft?
Enter the KEY you have prepared and requested from you.
And click to "verify" button. You will see next step If you have valid albeit old any product KEY for any version of Windows 7.
If you want learn to your computers processor (32 or 64 bit)
Right click the "My Computer" that on the desktop and Click on properties. You can see under "System" title
If you have 32 bit processor you should download x86 and if it 64 bit you should to x64
