twin tips are really good all round skis full stop. so they're great to learn on. forgiving and fun.
but ive said this to a lot of people in your position. learn to ski really well first. sure you can hit a few jumps and slide a few boxes, but dont get obsessed with park stuff to the detriment of normal skiing. the better you get at skiing the more comfortable you'll be in the park, not to mention safer. you'll learn how the skis react to certain conditions and weight transfers and you'll look a lot better too.
a friend of mine is a snowboarder and he spends all his time in the park. as a result his all mountain ability has suffered and he can't keep up with us when we're just skiing around normally. dont let that happen to you.
best of luck with it all though!