If you are going to use an adjacent room, then you need to look at what is having on the walls to be removed. Credit rating bearing, then you will have to put in a beam to support the burden. Most of my clients would prefer to see no evidence that the wall has been removed. In other words, they want a flush ceiling, which means you have to slice the joists apart and set up an in-ceiling beam. It can not that hard, but there is a particular technique to achieving this. I suggest you use a qualified remodeler to do this.