Nate,
over the years, I've been around or helped work with Goldens and labs of both sexes. The single most important characteristic is the breeding. It's not mandatory for getting a great dog, but it dramatically increases the odds of having a dog that will be easy to work with. If the genetics aren't there, you can't fix that. The rest is work on your part. If the dog is disposed to learning and pleasing you, likes to retrieve, and you put in the time and effort, you will have a hunting companion and pet that you will be happy with.
As for gender differences, size is the primary one. In the two breeds I've dealt with, females tend to be smaller. Since I hunt from a small boat, that's an issue for me. My 65 pound female is about all the dog I want. A 100 pound male would practically push the bow under when riding up there! I also used to think they were a tad more laid back, but my 5 year old female black lab will have the entire boat shivering when ducks are working in close, and I know that the first ducks of the year, she's going to break. She's pretty wired up.
I HIGHLY recommend the book "The 10 Minute Retriever" for the first 6 months. They do an outstanding job of emphasizing that you should work with the dog every day, not push too hard early, but lay the groundwork for good behavior by being consistent and letting the dog know where its boundaries are in his or her new world.