There's several options for butt pads, basically whatever fits you best.
Your boots - If they're comfortable, keep them. If they're hurting you then you might check into Nike, Vans, Celsius or another pair of Rides even. Boots are the single most important piece of your arsenal. So try on as many boots as possible and don't let money guide you when it comes to boots. You may have to spend a lot on them, but you might find a cheap pair that works also.
The bindings could need some upgrading, my advice is to try and find 2009/2010 Union Force if possible. Could even find a used pair as these bindings are bulletproof. The bindings are your #2 after the boots.... If they're comfy, keep them, if they're giving you pressure points, replace them now.
The board is the least important piece, but looks to be your weak point, assuming everything else feels good.
I recommend looking into Never Summer for a snowboard.
"When I do good, I feel good; when I do bad, I feel bad. Thatís my religion." - Abraham Lincoln
Moral of the story: If your going to rob people, wear a diaper.