I've used this website for the past few years to plan our road trips. It's great in terms of route planning, and the times and mileages indicated are accurate.
Free Trip
Just plugging in your starting point and your destination will give you the shortest distance between the two, but there is an option to select scenic routes and/or avoid toll roads.
There's also an option to display facilities along the route and another to display atlas cross-references, though I haven't bothered with those options. I'm just interested in the route and the time.