What is preferred in an emergency landing: a road or a cornfield? When faced with the situation of a power off emergency landing, how do you best select your location to land?

At what point is a road too small or the crosswind too great to attempt a safe landing and instead select a corn field or such? Should the road even be considered?

EDIT: Also, how does plane size and build factor into the decision?
Really depends on what you are flying, what's growing, what season and what the roads are like. Our Cessnas have used gravel roads a couple of times, either due to problems aloft or at the airport (bad weather). In the Alberta prairies finding a side road to land on is no problem whatsoever. 100 and 200-series Cessnas have fairly narrow fixed gear that can take an amazing amount of abuse, don't know about other types.

A real cornfield, with the corn fully grown, will destroy a light aircraft. The plants are 2-3m high with a hard, heavy log of corn at the top. Hit a couple of thousand of them at 100km/h..... (Skydiving centers in corn country have firm advice for landing in the corn: keep your legs crossed.)

Ripe canola is also nearly 2m high and is a bushy plant interwoven with it's neighbors. You'll probably flip over forward. Wheat is the best choice.