This depends on how far you plan on sitting from the television set. When you walk down the aisles in stores, a TV might look smaller there because of the big open space but it will feel bigger once it’s in your room. Which size to get depends on preference but a good rule of thumb is to leave a 12 to 15 foot distance between you and a 46”screen. If you’ll be sitting closer then go with something like a 37”, or even smaller if you need to.
If you really want to find out, bring a measuring tape with you to the store and get as close as you can to the screens before the viewing becomes uncomfortable and/or blurry. Then, measure that critical distance.