I have decided to get a Dog for Emma this Christmas, I am looking into different breeds, but since there are sooooooooo many...I figured I'd shorten my research time by asking your opinions...

Emma is a very active Toddler so I want a dog that is going to keep up with her and be patient with the occasional tail-pulling.  She's learning to be "nice and gentle" while petting but she forgets sometimes. 

What are your recommendations?