That's a nice collection of things to get you started with all kinds of experiments that will allow you to build some experience as a foundation for your robotic project.
You should seriously consider adding a few potentiometers to your toolbox though. Just a few 10K or 100K will do it.
They are really god for making experiments with analog input, and for controlling things.
After a while of working with the Arduino board you will probably also find yourself wanting some of the more specialized IC's like shift registers, multiplexers and stuff like that. These will allow you to increase the amount of inputs and output on the Arduino board. The good news is that most of them are very cheap. Other things you might want in the future is power transistors (like TIP120) or transistor arrays, (like ULN2003) and relays that will allow you to control stuff that draws more current than the Arduini board can supply.
I know you are going to have a lot of fun, i hope you will keep the forum posted on your progres 
MikMo