You don't really have "broody" breeds. Yes, Orps are known for being broody, but I've never had a hatchery Orp go broody. I'd be shocked if you had a broody Leghorn or RIR, since they have had the broodiness bred out of them for a very long time.. The oldest group are RIR's, Buff Orps, and another I was told was a white leghorn, but due to her size, I think she is a closer to a White Rock. She has also been consistently good at laying through this winter. Of the mid-aged girls, there are 3 Lt. Brahmas, a Silver Spangled Hamburg, an Australorp (we think), and a RIR. The remaining younger girls are mostly crossbreds, though a couple appear to be full Americana and full Austrolorps. I was told the other lines that were mixed included Marans, Orpingtons, and some unknowns. Lots of fun, but all consistently not interested in brooding so far! Hope that clears up the confusion. Thanks!
I've had every blue-laced red Wyandotte I've ever ordered from Murray McMurray go broody, if that helps! Also, Silkies will sit on eggs at the drop of a hat. I have also heard that dark Cornish are good mothers, so I got a few of those Spring 2012. I'll have to wait until Spring 2013 to see if they live up to their reputation.