I think most people around head towards the group of whitetail, liberty and roundtop. I took lessons at roundtop last year and my wife took one there this year. The instructors we worked with were good. I don't recall their names. If you sign up for a group lesson they will come out based on their schedule, but we haven't heard anything bad about the instructors at any of the three mountains.
One benefit to going there is that they have learn to ski/board days where it is $39 for the day including lift ticket, gear and the lesson. At the end of it you can typically buy an advantage card for like $45 which will give you discounts of 40% on lift tickets the rest of the year as well as your next trip free. That next trip includes the same lesson package. You will be able to take lessons any time you want the rest of the year as well. It is a pretty good deal and is worth it in my opinion. The card is good at all three mountains as well.
Welcome to snowboarding and I hope you have a blast.