DOS is the most less useful, anyway, DOS is not just a command line, but the ground of Windows 1.0 to 3.1 and 9.x.
1.0 was very colorful with little pics and meant for tiny screens.
Its better to run it through a windows emulator like MSVPC. (Microsoft Virtual PC)
It can be aimed for specific Windows and give you the recommended RAM and HDD space for a virtual HDD.
Its much better than destroying your computer with installing DOS.

You cant boot another Windows from DOS, DOS is too easy.
You would learn useful things from programming in yor own system.
Because DOS is YEARS out of date.
It was ended together with 9.x
Win95 and 98 used the DOS-kernel, which is a very limited kernel and not made for heavy systems, and would not use the full specs.
Its much better using the NT kernel, its filled with features.
DOS is easy enoguh coded to run on a ARM phone..

So, better stick with your own system, DOS is not of interest in programming, its another kernel and other systemfiles that cant run newer programs.