I have a ds 10 and a dd 6. The hotel was soooooo kid friendly. They have these "old" guys dressed as captains that greet the kids whenever they come in, and bring them to this huge globe in the center of the lobby, and ask them if they can find the "hidden mickey". Other times there's CM's giving out mickey stickers. Really nice people. We didn't have any issues. The kids LOVED it. As for counterservice. There is Hurricane Hannah's, but that doesn't have breakfast. They do have two sit down restaurants, and then a place right off the lobby where you can get a continental type breakfast. If you're on the
DDP, they count as snacks I believe. I never visited the counter service at BC, but they also have "breakfast" type items for counter service.
As for the EPCOT front gate. It is a lot of walking if you're coming from the gateway to get to space ship earth. But my 6 year old never complained, and we didn't have a stroller. With toddler's I'm sure you'd have a stroller, so the walk wouldn't be an issue for your little ones.
If we left the hotel at 5:30, it only took us 15 minutes to walk all the way from the room to dinner reservations at the Coral Reef...just to get an idea.
Our favorite part, besides SAB, honestey was the walking distance to Epcot. And after Illuminations, it was AMAZING to be able to just walk out of the park, while the rest of the crowd had to fight their way to the front.