Arabians, hands down. I've had the pleasure of working with and owning numerous different breeds and my Arabian was the most amazing horse I ever owned. And every Arabian I've ever ridden was amazing. I just love them.
A close second is Thoroughbreds, followed by Friesians because they're purrty LOL.
I love a good Quarter. Paints arent too bad either. Then again, National Showhorses are fun too..... hmmm. Arabs are by far easiest to train, Belgians are soooooo sweet ...... I guess I can't choose just one! I've had too many over the years of so many different breeds, and ridden enough different horses, that there really is no ONE good breed. They've all got their high points.
Walkers and any sort of Draft. I love the big breeds.
Yay for walkers! Definitely one of my favs as well, now that I am lucky enough to own one. Their running-walk is amazingly smooth, and they have the sweetest, gentlest dispositions (even if they are sometimes gangly and mule-eared like my baby ).