When you were house hunting did you ever walk into a home and it simply just didn't feel right, and it made you slightly uncomfortable, and you didn't know why?
Sometimes it's just a matter of the rooms not being used as they were intended to be. The dining room might have been changed into an office or a kids' play area, or a spare bedroom into storage. Of course when you are living there you can design your home any way that you want. However, remember, this non-traditional setup can leave potential homebuyers with mixed feelings. They logically know that it's supposed to be say a dining room, but they might have a bit of trouble envisioning it that way.
The point is if you are selling a home, you really need to consider putting your rooms back into their original purpose. It might sound silly, but it gives the potential buyer a gut feeling that everything is exactly how it should be, and you won't miss out on a potential sale.