Morning All, we are staying in Watford as well, after speaking to other people who have stayed in Watford they have said get an Oyster card from the Post Office.
This allows you to travel all over london hassle free without the issue of queuing for tickets at the tube stations.
Tube Trains run every 10 - 20 minutes from watford to wembley journey time around 25 minutes max, put an initial paymnet on card about £10.00 this allows un limited useage on the underground plus the kids travel free on these cards.

by the way I have 3 boys so it work for me & is cheaper

cheers The Tinks

Phew, just checked and i'm good. I'm on London Overground at that point.

Don't be scared about replacement buses, you still just go to the station, jump on a bus, they run in higher frequency than the trains and will only put about 15 mins extra on your journey

Which tube station is the one at the end of Wembley way? Got the wrong one last year and ended up walking past a Primark, the missus sulked so we had to go in to keep her happy!!

Wembley Park is the one on 'the way'
the other is Wembley Central

Oh crap!!!! Hope OH doesnt read this!!