hammy:
Not the answer but ...For this sort of task I would use an external pull up resistor of say 1kohm - the internal pull up is a high value and you can get problems with long lead length to your switch .
Try running the digital input example and get that working
So I initially had a 33 ohm resistor on my board but was told to remove this and us a internal pull up resistor. So what is the reason for using a external one over and internal one? Just curious.