I will address the topics by parts:
Windows vs UNIX for application development
There are basically two types of operating systems in mass use in the world today: Windows w UNIX (Linux distributions, Apple OS X, BSD). So’s of these two types are extremely different, solve problems in completely different ways and have quite conflicting usage philosophies.
I will not go into detail about these differences here because I think it does not fit in this topic, but it is very useful to keep in mind that there is no way to directly compare the two and choose a better one: they are different pets, each with its qualities and defects; point out that one is better than the other without taking into account the context where they are being used would be stupid.
Operating system for server
The overwhelming majority of web servers run Linux, because it is the most ubiquitous operating system with the most support for running web applications and for being completely free and free of charge. Obviously there are many applications running in Windows environments, especially those that use Microsoft technologies, such as the platform. NET (C#, ASP.NET, VB.NET) which was specially made to run on this system. In general the Windows environment can be a little inhospitable for some types of platforms - try running a Ruby application on Windows without pulling out a few tufts of hair trying to debug the torrent of problems that occur :)
Operating system for development machine
If you develop applications using Microsoft technologies (.NET for example) there is not much choice: the solution is to use Windows. Although there are some efforts by Microsoft to bring their platform to other operating systems (such as Visual Studio Code, released this week by Microsoft), only Windows offers all the support you need to develop these kind of applications.
Whether you develop apps for iOS or OS X is even worse: you’re forced to use a Mac.
Now, for development in other more open technologies there are more options. PHP is a good example: you can develop web applications using PHP on both Windows and UNIX systems. Which one you will choose depends very much on personal preference. If you prefer command-line tools, you will usually opt for UNIX, since the command-line environment and tools available on that system are much superior to those present in Windows (a great example are package managers: installing libraries and dependencies on UNIX systems is extremely easy using tools like Homebrew, APT or Pacman; whereas in Windows this can become an arduous task, given that the tools available are not as advanced and use a very different philosophy). If you prefer to use IDE’s and other visual tools there is greater flexibility, and using Windows does not become as problematic.
There is also a great influence of the community. A good example is Ruby: the overwhelming majority of Ruby developers - not to mention everyone - use UNIX (Linux or OS X) environments. This happens by a number of factors: although possible it is extremely problematic to run Ruby applications on Windows; most Ruby tools use the command line and are inspired by the philosophies of the UNIX environment. So it’s almost obvious to use Linux or OS X to develop this kind of application.
Just by way of illustration: most developers I know use UNIX - some Linux distribution or OS X - but this is a reality of the kind of application I develop and the community I’m in.
Dual-boot
You can do dual-boot on any computer, no need for a specific computer to run Linux. Modern distributions have great support for various types of hardware and we have more progress on this issue each time, so you should have no problem running a Linux distribution on current hardware.
a comment nothing to do but , change college.. I have nothing against MS, on the contrary, MS use as a primary tool, but at college level, you should be in a more open environment where you are not "stuck" to a brand or product. The faculty where you are will only form people "technologically engineered"...
– Daniel Omine