Alrighty, when it comes to picking a snowboard your height is basically irrelevant, but your weight is most important, followed by your riding preferences and your boot size. Just from your weight and boot size I would put you on a board around a 158 to 162. You could probably go down to 154 or 155 Wide if you were looking for a shorter board to mess around in the park. Each manufacturer should have recommended weights for the lengths of their boards and they are usually pretty accurate. I have several different setups for me. I'm 5'10, 180 lbs (81kg), size 10 boots. One of my boards is a 152W and another is 158 not wide. If you're interested in riding a lot of switch then a twin or directional twin shape would work best. Since you are in the beginning stages I would recommend a reverse camber or hybrid camber profile for the board as they will be more forgiving than a traditional camber board.
I always suggest investing a little more money in a good, comfortable pair of boots since often times your boots will be the determining factor in whether you have a good day on the snow or not.
Hopefully that gets you started. Beyond that you'll probably get as many different opinions as the number of people you ask