My fiancé will be coming down for a visit for a month soon
Am I wrong to assume this is your first face to face meeting as well with this few months on line relationship/engagement/marriage?
You don't have to be old fashion to say What the heck, with the speed you are moving at. Plan for the best, everything will go smooth, but expect the worst, CHAOS, because they will be freaked out by it all.
I suggest not overwhelming them all at once, and only give them SMALL bits, starting now, and slowly building up to the truth, as first they should be given time to wrap their head around the fact you have a guy. The rest can come later, but the more you put it off the less time you will have to prepare them.