HI! I snowboard with my 16 y/o son and it's a great time for both of us. It's nice to have something we can do together, and lucky for me I learned before him so he's working to keep up with me instead of the other around...at least for now. haha
As for eqpt. I suggest you start looking for a great pair of boots and work your way down from there. Rental boots, just like rental boards, can help you decide what you want to buy. When I first started riding I rented boots and boards for two seasons before I bought my own at the end of the second season. By then I knew exactly what I wanted...and what I didn't want. I also had time to look around for great deals and was able to buy my stuff on end of year closeouts. My board was 1/2 price (Burton Feelgood) with Lexa bindings that were also about 1/2 off. It was all brand new and I haven't regretted the money I spent on rentals.
If you have a large foot (size 12 or bigger) try to rent wide boards. My son wears a size 12 boot and he can ride a regular board, but just barely. His next board will be a wide one and he'll keep the current one as a back up board. By some ski/snowboard specific socks if you don't have any already. I didn't think they'd be a big deal but once I had some I really enjoy them.
There are some great wide boards made for larger people (164 and bigger for your size I'm guessing). If you pick up the idea after a few rides you might consider buying a used beginner board that has been taken care of and then upgrading to a brand new intermediate board in a year or so. As long as the used board was cared for and doesn't have any core shots or wasn't abused it can be a great money saver while you are still learning how to ride. After riding both extruded and sinstered boards I recommend a sinistered board if you are just planning to ride greens and blues. I have one extruded board and I get frustrated at how often I have to wax it. I can feel how slow it gets after just one full day or riding. It's an older board so maybe that plays a part but I want my board to glide across the snow w/o a lot of drag.
I hope some of that helps. There are tons of opinions about eqpt. and ten of us may give you ten different answers about what is best. That is why I recommend renting for a season or buying used at first. I do believe some people get turned off of snowboarding because they buy the wrong eqpt early on. Read some of the info on this site and read lots of reviews on the boards, bindings, and boots you think you enjoy riding.