Ok Kim, I am assuming that you are too young to understand the paint gun/travel thing, but I have to go with your problem a little.
I want you to know that Ron is right, painting a perfectly good brick surface is a danger. Brick is a maintenance free product and painting it can result in "poor results"
However, I am assuming that you have an "ugly" brick or you wouldn't want to paint it. I don't mean just the usual "not up to snuff" ughly, I mean the type of ugly that comes with looking at the south end of a north bound moose. I mean the kind of ughly that bothers you so much it keeps you from eating for fear of loosing your breakfast. You get the picture.
Solution #1, paint the sucker. If it is keeping you from beautifying your home in a manner you wish to become accustomed to, you gotta do it. Just remember that you have to prep the surfaces correctly. Usually this means cleaning properly and then you are off to the paint store to buy a product that loves to bond to brick.....a "cementitious coating" is the usual term. The type of coating could depend on the type of brick. You have only to talk to your paint store to find the correct product. I would talk to a couple of paint stores if you have that luxury. Just remember, when and if it does peel, don't blame Ron or I. Actuallly, painting brick is done all the time, and considering it is "inside" your home where it gets no weather, I would not be too afraid to do your thing to the wall.
Solution #2 (can really be a Godsend if solution #1 fails): cover it with another material. You could cover it with wood paneling, gyp board, false brick or stone, stucco, etc. Just remember to keep combustable materials away from the fire box opening according to code. There are obvious advantages to this solution..........flexibilty. You can add electrical to that "perfect" piece of art that you purchased at the flea market, or add storage, or what ever. Just remember, you do not have to keep something ughly if you don't want..........unless you are married to it.