C language is pretty good for high performance, but it has strict standards to follow and is very easy to mess up if someone is learning from it.
Then again the learning curve is really short if you already have programming experience in other languages, like Java, hence you comprehend it more easily.
Java is a Object Oriented Programming language that focuses on Objects and Inheritance the most, hence for beginners, will take a good chuck of your effort to learn it somewhat.
It isn't hard per say, but the performance on Java is what some programmers call "Crap" at most. Java functions and codes can take up more memory and cpu than necessary, no thanks to the plugins and stuff you throw in to code as 'easy' as possible, only to be prone to bugs that way.
C++ Is sorta the equal ground between Java and C, except from what I see, the standard it uses is a bit alien to me, as C and Java would have a few similarities with referring and pointers, but with C++ it ends up utilizing a BRAND new set of delimiters, etc. To make comparisons or links to codes. Basically learning it's standard is a bit harsher than C if you had Java experience, but it's not a cliff hanger.
C# Is the newest language that all students and newbies are starting to use this generation, over other languages, but perhaps it's a bit more advanced. So in my College Program, they teach Java early on to emphasize OOP and Object Oriented Design and Analysis, then move you onto C# for a more advanced level of Object Oriented stuff.
Java is the easiest to learn, since it emphasize the most in a spoken language... But for the cost of that, performance loss in large program is more costly than C/C++/C#.
You may also need to keep a head up for terms like Low Level languages, and Assembly Language, since the languages I mentioned above are all high level languages.
Low level and Assembly is much harder, and the posts before me probably relate more to them.
If you have little to zero programming experience, I would suggest high level languages over them, for the sake of simplicity and not to be pressured by programming communities that hypes up the languages they know and use. >_>
You can ask about programming at
http://www.devscorner.net/forum.
It's activity is low but me and the guys there do post and read stuff from time to time. At least until they started getting busy at whatever they are doing and such.
In the older forum, there was plenty of talk on programming...