I imagine the *difficulty* of growing up with 2 gay parents can only come from two main sources: 1) The child's environment (e.g. school, friends, the community) and 2) The child's home (e.g., the parents and their parenting style). So first I would consider where you would plan on raising a family.
I hate that there are only a few giant gay havens in the U.S. --San Francisco, NY, Ft. Lauderdale, Provincetown, West Hollywood etc.-- because that leaves the rest of us out. But I imagine these can be good areas to look around when you're looking for an open minded city or suburb where you can feel at home. However, not everyone can afford to live in these cities as they tend to be expensive, and even difficult to adjust to. That said, I would spend a lot of time looking for a place that fits *just right* for you and your future family. It's a difficult search, but trust me it's worth the effort.
As for parenting, I'll say this:
Someone once asked me and a few friends about what she should tell her kids about a gay couple if she runs into two guy's kissing; she 'wasn't homophobic' but she just 'didn't want her kids to have to be exposed to that so early.' I never got the chance to answer her, but if I had a second chance I would ask her how she learned to become 'okay' with gay men and women; whatever that moment of realization was for her is exactly the sort of explanation her kids deserve. She doesn't need to get down to any extreme details; people would be surprised at their children's capacity to understand love & friendship.
Children listen and when it comes to difficult questions, as long as you believe that you have good beliefs/convictions on the given issue, explain to them what you yourself learned a long time ago.
Plus, it's never too late to ASK for help :)
Corny as it sounds, when kids come into the picture, you figure out what you need to do very quickly; fears fall away.
Personally, I'm terrified of bugs.
But when taking care of my baby cousins a few weeks ago. I did what I had to do lol
If you're called to have kids, I think you'll find a way to be there for them. And the world isn't getting anymore conservative.