My DH and I stayed on the Queen Mary some years back. So did Laura (Oceangoinggal) on the Cruise Talk Cafe. You could pm her, too. We both agreed then that the Queen was not being well cared for hotel-wise.
Do tour the ship, but I would not recommend you stay on her. There are many places to stay in the area. The food was first rate, especially the Sir Winston restaurant. There were no fast food places, but that could have changed.
There have been plans to buy the Queen, but I don't know if any of them came to fruition. You might try to Goggle it. I don't know who owns it now. BTW, I thought she was expensive, but that's just my opinion.