I mean it is not reccommended for games.
It is like running an OS in a VM and expect everything to be as fast as running one natively
I aknowledge that Android uses Java, but I don't game on Android :^)
And it seems that Firefox dropped support for Java
Also, it is worth mentioning that I hate Java
Actually an OS ran in a VM can be as fast as running one natively.
But that's thanks to CPU virtualization features which essentially allows you to execute virtualized programs directly on the CPU while staying within the sandboxed environment.
Java doesn't have that benefit, and it also doesn't compile to machine code, but bytecode, which is always going to be slower.
JIT helps immensely though and you can create some fairly complex things (including games) in Java that don't appear to be noticeably held back by being written in Java.
I think Java is a good starting point because it's easy to learn and it's similar to C# in many ways which is one of the most popular programming languages today and a useful thing to know. Java itself is losing popularity though and might die off completely eventually, but is still useful knowledge for making mobile apps for as long as Android keeps it on life support.
Really for NDSi and PC because I don't know jacksquit on how to code and I really wanna make this game I thought of (Luigi mansion but 2D) so If anybody could help please do so also Playstation2Store
Don't start with DSi as it pretty much requires C/C++ knowledge and that is not the best language to start with.
For PC game development you have many choices but C# is a good one to start with as it's easy to learn IMO and can be used with both MonoGame and Unity and probably a whole host of wrappers for different game dev libraries.
Maybe don't start with games right away but make some simple programs as game development is a whole lot more complex than programming simple utilities.
Once you are familiar with programming and you understand the basic concepts of a higher level language like C# or Java or even Python you can then move on to C/C++ if you wish.
Game Maker is not a bad thing either, it greatly simplifies getting into game development even if you have no previous coding experience and games made with it can run on most platforms in use today including Android, iOS, Windows, Linux, probably Mac, Windows UWP (X-Boner, Windows Mobile, Windows Store apps), and PS4 although a lot of those require expensive licenses unless you pirate it, it won't do a whole lot to prepare you for lower level languages like C/C++ but if you learn GML scripting that will help you understand the basic concepts of programming and make it easier to learn proper programming languages.
I had played around with other languages before but didn't really understand them that well, and it was thanks to Game Maker that I really got into programming and eventually learned several other languages.
Game Maker games can even run in HTML5 these days so you can run the same game on all those platforms and even as browser based games, although more complex games may run slowly in HTML5.