We did the breakfasts at both H & V and Chef Mickey's on our last trip. We enjoyed both breakfasts equally! They were both excellent. Excellent food AND character interaction with the kids AND the adults!
As far as H & V, they do some songs and dances which some kids love to get up and do with the characters, and others enjoy watching from their tables. They do this on both sides of the restaurant, 2 characters and workers from the restaurant on each side of the restaurant, so everyone can see and/or participate! It is done very well, and done often enough that everyone gets to see it at least once. But not so much to make it annoying. They have a nice balance. Characters also come around to tables and are very good with the kids. If your kids know Playhouse Disney, they will know these characters, although JoJo's Circus is no longer airing on Playhouse Disney so I wonder how much longer she will be there, or if they will replace her with another Playhouse character. Little Einsteins are still airing and are very popular!
The food at H & V for breakfast was excellent. They had the basics, like bacon, eggs, Mickey waffles (a big hit with my kids), hot and cold cereals, fruits, danish and pastries. But they also had more unique choices, but I am sorry, I can't remember the specifics at this point! I do remember though, that they had dessert available at the breakfast buffet! There was really something to eat for everyone! The service was also good, the waitress kept our coffee filled (a MUST for DH and me!), cleared plates in a timely fashion, and she was very nice to the kids. We had an 8:05AM ADR and we got out of the at 8:45, 15 minutes before rope drop! And my son participated in the dancing with the characters! Yet we did not feel rushed at all. So it is quick but not rushed.
I highly recommend H & V for breakfast! We are going there again on our next trip!