I would argue that LISP is probably the easiest of those languages to learn, actually. Well, maybe Python, it's close.I would add on/respond to this and say that writing code that is hacked together can cause you huuuge problems and wastes of time down the road, if it's a project of any size.
Also, some languages can probably be a lot better than others for beginners -- simplicity of certain Python or C# operations versus C++ templates and operator overloading or (to be silly) LISP. Or Perl (haha).
Also also, I would say first make it work, then make it work right, then make it work fast. Premature optimization can be the root of all evil, unless you're confident that something you're doing is going to be key for performance and needs benchmarked right then to make sure it's feasible.
Of the four languages you listed, C++ is easily the most performant, but I don't think that's news. My initial instinct would suggest that C# is almost totally useless for game development but I'm probably wrong about that.