I agree with Indjo. I live in an area that has some decent shopping areas that are about 45 minutes away from where I live. My mom lives about an hour away and my sister lives about 2 hours away. Some days, a 45 minute drive may seem like nothing to me.
Another thing to take into consideration is where I'm driving to. If I'm driving to work, I don't want my drive to be over 30 minutes. If I need to drive more than 30 minutes to work, I should consider relocating. I don't want to spend over 30 minutes driving to work knowing that I'm driving to work. It could also take a toll on me since I work long hours or if I have to go in for a morning shift (YUCK!).