generating C++ executable for Windows/ GUI question

[felson]

I wrote a C++ program which I compiled on my Mac via gcc. It has a simple command-line interface. Is there an easy way for me to compile on my Windows PC and send the executable to others?

Also, I'd like to add a GUI for the program -- nothing fancy, just some clickable buttons and a window for text output. Does anyone have somewhere I can look to get started?

Thanks!