We have just purchased a ranch home. Do you think that taking down a wall between the dining room & living room and putting up columns would look odd and out of place.

 

First question: Is it a bearing wall? If it runs in the same direction as the ridge on the house roof, treat it as a bearing wall. You would need the proper sized beam and posts (spaced properly) to support the ceiling joists. Get bids from a couple of contractors to do this, and ask questions (like 'what sized beam and posts they would use' and 'post spacing'. And do it with a bldg. permit. It's structural.