I have met many Labrador/pittie mixes, and they all seem to be great, fun dogs! Can't wait to see pictures of you newest family member!

As for dog parks/walking, I say go for it, but be sure to remain calm, if you seem nervous at all, she will sense your fear and might behave in ways you don't want her to behave. You will never know if she is dog aggressive or not if you don't take her for walks or take her around other dogs.

For the dog park, walk along the fence line surrounding the dog park with her for the first visit, to see how she behaves. If she growls, barks aggressively, jumps, and pulls aggressively towards other dogs, it is wise to not take her inside/let her around the other dogs. If she seems happy, (wagging her tail, yipping with excitement) then go ahead and take her in. It might be a good idea to keep her on the leash for the first few minutes when and if you do go inside after you have observed her behavior, just to be sure. Some dogs don't get along with dogs of certain traits, it's very interesting, actually. The key to knowing your dog is being able to read his/her body language. This is very important!