Buy the leg you need to Nice. The amount you spend on the ticket will be saved in the amount of anxiety you save making the connection.

It is not necessarily a difficult connection by train, but the two airports are on the opposite sides of Paris, so most people suggest allowing at least 3 1/2 hours. But the real issue is that you have to worry about your plane being late, strikes or slowdowns on the RER, etc.

If you fly AF all the way, you become their problem if the plane is late. We had a tight connection owing to a late arrival from Marseilles once, and they picked us up in a car/SUV at our arriving plane and drove us to our departing plane. We never entered the terminal, and our luggage came right along with us into the hands of the waiting baggage handlers.

The easiest way between the 2 airports is by Air France coach. Allow 4 hours.

But I'd take the train. You can get a TGV from CDG straight to Nice. No switching airports in Paris and you arrive in the center of Nice. It takes about 5 1/2 hours. Tickets bought 3 months in advance can be as little as 30 euros...

You can through-book the train at the same time as the flight I believe... best to check with AF on this and if it can be done with FF miles.

"- Would our bags be checked through to Nice or would we have to get the bags at CDG and re-check them at Orly?"

"I assume that to check the bags straight through to Nice with no issues, we would be best off purchasing the Nice leg on Air France also.""

They won't check your bags through. You will have to deal w/ them yourselves.

If the OP buys seats on a connecting AF flight from CDG to Nice, their bags will be checked through. But not if their flight leaves from Orly.

I agree with Ackislander; buy the seats to Nice. Then if your first flight is delayed, Air France will take care of you. It will make a much more pleasant start to your trip.

Oh -- of course -- my comment re luggage was about the Orly flight.