We got to Dubai lots and have been several times in October half term. However the cheapest we have got it for a family of 4 (We also always fly Emirates) is £3900 for hotel and flights. Its an expensive week as the weather is hot but not roasting hot and its a way of getting winter sun so they put the prices up.
So instead last year we went to Abu Dhabi and it cost £2100 for flights and hotel. We stated on Yas Island so near the race track (which was amazing-kids could ride a pedal cycle around it at night!), Ferrarai world, Yas Waterpark and the mall. We also went to the mosque which was beautiful. Worth a thought if you love Dubai but want something slightly cheaper.
We've also driven between Dubai and Abu Dhabi (it's about an hour) so you could also go for a day if you fancy it.