Best bet is going to be to just try them on when you get to the store. All those things you picked out will work as long as they fit you right. Since you are young you will still be growing this year so make sure you leave a small room of adjustments in you outerwear.
As for those you listed it comes down to personal preference and fit. Burton has a couple different types of fits so just try on everything. The boots are decent IF THEY FIT YOU CORRECTLY.
Plan to spend about 80 percent of the time with your boots though so start with them.
Mostly you need to pick out your style for yourself. If you need to skimp on cash anywhere do not do it on boots.
Burton does make good outerwear so anything will work for you there. Not sure how the staff is there but make sure you ask them any questions you can come up with while you are there.