Proper first world problem
I skied as a kid but snowboard now. I'd probably like to ski again at some point but it seems like a waste of time on snow when I could be snowboarding as I'd have to re-learn everything.
You know deep down which you would rather do, so do that. I'm a standing sideways kinda guy. If you do pick snowboarding though, don't call it boarding
The following are generalisations:
Skiing is faster, but there's times when snowboarding is too fast for me "fuuuuuu..."
Skiing you have more control (two edges vs one)
Snowboarding allows you to ride powder sooner
Common snowboarding injuries are broken wrists, cocksys (sp?!), face plants. Expect to fall a lot when learning to snowboard.
Common ski injuries are buggered up knee ligaments (ACL is very common)
Skiing seems easier to learn the basics and get down the hill, but harder to master
Snowboarding basics are quite tricky but once done, you can get pretty good, pretty quickly. e.g. Carving is an easy unlock.
Snowboarding seems to have more fun easy-unlock tricks to play around with (butters, prezels, 180s, reverts, tail blocks, etc) which are great fun, skiing has some, but they look a mess with poles and sticks everywhere.
Lifts are crap for snowboarders.
Snowboarding is a pain in flat resorts, if you are good you can bomb through the flats, you will deffo piss people off doing that. The flats are usually blues and greens, it's a loose-loose situation.
And the most important reason to snowboard:
I'd probably just do what everyone else is doing. I've gone mainly with snowboarders but there's often been skiers in the group too - it's all good. Whatever you do you'll have a blast.