Nope. Santa comes down the chimney and leaves presents on the regimnetal square for each and every one of you. The permanent staff invite you back to their houses for Christmas lunch, and a go at their wives/daughters or if you are Household div, sons.
You run for a bit, then a bit more PT, followed by some PT, oh yea, make sure you're boots are gleaming and you are well turned out for church parade, otherwise you'll be spending christmas in the pokey.
Just to save your worries, the Training Centres close down for Xmas and it is generally 2 weeks on leave prior to going back and completing training
A lot of people seem to have this hang up about joining the Army just before Xmas, most dont realise that it is better to get ragged around a training area when its cold than it is when its scorching hot (did i say that all training areas no matter what get sun booked for the summer? ) and the training is broken up by Xmas leave, so instead of getting a long weekend at week 7, you normally get to go home for 2 weeks instead