Introduction:
Microsoft Windows is a popular operating system developed by Microsoft Corporation. It has evolved over the years with numerous versions and updates. In this response, we will discuss when MS Windows operating systems were proposed.

Early History:
Microsoft's first attempt at an operating system was MS-DOS (Microsoft Disk Operating System) which was released in 1981. MS-DOS was a command-line based operating system that provided a platform for running software applications. However, it lacked a graphical user interface (GUI) which made it less user-friendly.

Proposal of Windows:
The proposal for a graphical user interface-based operating system came in the mid-1980s. In 1983, Microsoft announced a project named "Interface Manager" which aimed to develop a GUI-based operating system. The project was later renamed to "Windows" and development began.

Windows 1.0:
The first version of Windows, Windows 1.0, was released on November 20, 1985. It provided a graphical user interface with overlapping windows, icons, and a mouse-driven interface. However, it still relied on MS-DOS as the underlying operating system.

Windows 2.0:
Windows 2.0 was released in December 1987. It introduced significant improvements over its predecessor, including support for expanded memory, overlapping windows, keyboard shortcuts, and improved graphics capabilities.

Windows 3.0:
Windows 3.0, released in May 1990, was a major milestone for Microsoft. It introduced enhanced performance, improved graphics, and a more advanced user interface. Windows 3.0 also marked the transition to a 16-bit operating system.

Conclusion:
In conclusion, MS Windows operating systems were proposed in the mid-1980s. The first version, Windows 1.0, was released in 1985. Since then, Microsoft has continued to develop and release newer versions of Windows with significant improvements in functionality, performance, and user experience.