The only way to open such programs is decompiling. You will be able to see the code. However the programer is able to protect the source to make it undecompileable.
I'm actually using visual basic to make my programs.
Easy syntax , easily understandable. I'd rather start learning vb than c++ if y'only into doing trainers or smaller tools. If you are into programming real hacks such as aimbots & esps, c++ is your language =P