Yes, the fixed taxi fare goes into effect in March 2016. It will be either €50 or €55 from CDG and €35 from Orly depending on the part of Paris you are going to. Most cabs will only carry a max of 3 people although there are taxi vans that can carry more.
It can be faster to take the RER to get to your hotel depending on traffic. And it costs €9.75 per person for the RER part from CDG. You will probably need to take a taxi or the subway from where the RER leaves you to your hotel.
The Paris subway is fairly easy to navigate and not overly expensive. I managed it with zero knowledge of French. The hardest part was buying the subway ticket with my non-chip credit card and having no coins to feed the ticket machine. The machines have been improved since my last visit and do also take Euro bills as well as coins and credit cards.
Other options are the many buses that can take you into the heart of paris. The fares vary, but are around €10 per person.
Suggested that you avoid the shuttles since they seem to be unreliable, especially if you pre pay.