Brown Leghorns are my favorite, because they have beautiful coloring and they are great egg layers. The Brown Leghorn's colors help it hide better from predators than the whites. All the leghorns are quick and can fly short distances to get away from predators. This makes them a good choice for free ranging.
The name Leghorn is an anglicisation of Livorno, the port city in Italy where they were shipped from to the United States. Many people in the United States say "Legern."
I prefer the look of the single comb varieties, but if you live in a cold region the rose comb varieties are probably a better choice because the comb is less likely to get frostbite.
Here is a website for the American Brown Leghorn Club: http://www.the-coop.org/leghorn/ablc1.html
I especially like the Single Comb Light Brown Leghorn. Here are some pictures I found.
The second male looks like an English or Australian bird. Their Leghorns are a very different type with much bigger combs, wattles, and front ends and do not have as much as tail as American Leghorns.