Hi Keeley
I don't want to burst your bubble but we are big fans of DLRP and have been about the same number of times as you since 1994. We have been at many different times of the year. However, in 1997 (I think) we went from 26-30 December. It was AWFUL. Worse than Oxford Street on Christmas Eve. You could hardly move - even in the shops, and we did 4 rides in a whole day. 2 hour waits were the norm (pre fast-pass days). If that had been our first visit we would never have gone again.
However, last year we wanted to see the park at Xmas so we went from 12-15 December and it was great. Not crowded at all. I think the most crowded time of the year is between Xmas & New Year and I'd never go then. I think you too should avoid that time. If possible, go in the first 2 weeks of December - it's all done up for Xmas, not crowded and there are cheap deals on. Hope that helps.
Sorry, but I don't know anything about the Tinkerbell dinner thingy.
