Learning to snowboard isn't that hard. Don't hop in the park, don't hit the diamonds, don't cut through trees, etc., on your first couple runs/days. If you know someone that's good at snowboarding, hit a couple green squares and by the end of the day you'll be able to make it down without too much of a struggle.
If I were you I'd rent the first couple times as well. It's more expensive, but if you find out you don't really like snowboarding/don't want to do it anymore (I don't know why you would...), you won't have $350+ in gear laying around.