Just to let you know, if you program in C it doesn't matter were you write the code.
Only the compiler you use, or some system specific code will limit you to a system.
(Write it on paper if you want...)
Most simple programs could be compiled for most systems, not the GP32.
The GP32 just uses other calls for writing to the screen etc.
Also knowing other languages will help you to understand C, try java-script or so.
This will teach you IF/WHILE statements, that are most common in programming...