Here is how you can download Windows 7 Disc Images via the official channel legally, and also create installation media such as a DVD or bootable USB drive to install Windows 7:
Right now, Microsoft still allows you to download Windows 7 ISO images directly from their servers through the software recovery page. Sadly, Microsoft removed those links in 2014. In such cases, Microsoft facilitated digital versions of Windows 7 ISO through Digital River, the official distribution partner for Windows 7. Originally, Microsoft didn’t bother to provide the ability to download Windows 7 OS in any format unless you purchased a retail version license online. Download Windows 7 SP1 ISO – Directly from Microsoft
