As for which of the 7 ½ habits I think would be hardest for me, I would have to say that actually setting the goals would be my choice - I often have many different ideas going through my head all at once, and trying to pin things down is not something I'm good at.

In regards to the easiets, that would be having fun - I try to make everything I do interesting or atleast lively - it's better to enjoy life than worry about things.