Buying tickets on line for TOTR may help you avoid any queues at the entrance but, as I said in an earlier post I walked straight in as there was no one waiting. It will most probably be busier though in September so it could save you some time.
For Woodbury I haven't been there, I don't know if buying a ticket ties you to a date and time, if it does and you want to change your plans after arriving in NY then you may not be able to. It may though be an open ticket that you can use at any time. There does seem to be lots of coaches to Woodbury during the day so I doubt whether you would have problems getting a seat on one, but again having a prepaid ticket would cut down on queuing.

Not much help I guess, hopefully someone who has been to Woodbury will have more info.

http://www.newyorksightseeing.com/tourpage.php?item=WC

Have a great trip, super destination for a short (or longer) break.

Thanks Judith, sorry if I repeated myself