I looked back on your question and It read which is the "easist" to use. To me all three of those are tough. I have all three and am not very good on any. I have gotten the furtherest on Illustrator. I am not sure what you have in mind for buttons. There are a lot of sites where you can get free, premade buttons. That is the easiest. Based on your question I am assuming you don't have any of those and they are all expensive programs to use one time to create a few buttons. You can make any graphic into a button easy enough and avoid the programs all together.