Preface
Unless your robot is completely autonomous, you'll probably want a nice, centralized, and graphical way to control it. Really, you can use anything that can output to serial. Python is a really easy way to accomplish this with minimal programming thanks to its easy syntax and some well built libraries like pySerial, Tkinter, and Tornado.
Python provides a easy-to-use library called Tkinter that allows the user to make GUIs. This is a good way to get a nice windowed GUI on nearly most platforms (Windows, Mac, Linux). It requires minimal setup, and is relatively simple to use.
Another option for a Graphical User Interface is Tornado, which is a web server. With a web server, you can control your system from anywhere with an internet connection with anything with a web browser.