It's a legal connection. It's over 30 minutes. Charlotte isn't that big of an airport, and in all honesty it really only takes five minutes to get from the far end of terminal B to the far end of terminal C. When you check in at MCO the will check you in the entire way through, so once you find your connecting gate you should be able to simply get on the plane. Remember, often the flights arrive early. Because the equipment and crew is probably finishing the day in BUF, they *might* hold the plane for you, but of course there is absolutely no guarantee of that.
If you get to the airport for the earlier flight and there are available seats, they will give them to you with no additional charge. It's a win/win situation, you are less likely to be stranded in CLT and they now have open seats on the later flight that they could possibly sell. They generally will give you standby tickets for the earlier flight, and not confirm you until after all confirmed pax are boarded. And it's likely you will not all be seated together. If you want to be assured of that, you'll have to change your flights now, and pay the penalty.
Keep in mind that delays caused by weather or air traffic do not entitle you to a room for the night, or any other compensation, so if youa re stranded in CLT for the night, you'll probably have to pay for your own room and other associated expenses. (Only being involuntarily denied boarding entitles you to compensation)
My best advise is to not carry on too much stuff, try to get seats as close to the front of the plane as possible, and if the flight is running late, let a FA know that you have a tight connection, they'll often assist you in getting off the plane first. Also, they can usually tell you what gate your flight is landing at and what gate your connection takes off from. You can look in the back of the US Airways magazine and there is a layout of CLT with the gates shown, so you can get an idea of where you are going.
Anne