If by 'Queens facility' you mean Queens Grill then you will be supplied with wine, spirits and beer free of charge in your cabin fridge. On your first day just specify your requirments and even brand and they will deliver to your cabin. In the bars and restaurants the drinks and wine are much the same as in England, perhaps a little higher as they include a 15% service charge - by memory wine starts at about 20/30 dollars a bottle (£10-£15) and goes up to what you want to pay just as in the UK. I don't think they have house wine but they do have a good selection and a genuinely wide range of prices. The main thing is that you are going on the best ship afloat and will have a great time - yes you will probably spend more than you thought but you will have wonderful memories, especially in Queens Grills, which is I believe incomparable with any other ship. If in doubt read the Berlitz cruise guide. Have a great time and don't worry about the alcohol prices or anything else for you should be in paradise!!
Travelled on QM2 last year and QE2 in October so think the pricing would be the same on both? Anyway drinks were very reasonably priced, currency is US dollars. We paid $20 -$30 dollars for a bottle of wine (of course you can pay much more if you want to) and cocktails were from $4-$6 dollars. Hope this helps.