The choice of golf balls is something that you don't need to worry about right now. Go to Wal-Mart and grab a pack of the refurbished ones they sell...the ones that have about 8 different types of balls in it. You will hit a $.75 ball pretty much the same as a $3.00 ball, so save some money...
As Casey said...just have fun for now. You are still very green at the game and what you lack most is muscle-memory so you won't be able to make a consistent swing time after time. Hence, the "ugly" shots with a handful of decent ones. Once you train your muscles and coordination to swing the...