We went in 2016. Roland Garros is in the southern area of the Bois de Boulogne in the 16th Arrondissment. As this was our main goal for our two days in Paris, we stayed in a hotel in the 16th and simply walked to and from the venue.
We have been to other major tennis tournaments (US Open, Australian Open) as well as BNP Paribas. Our preference is to go during the early rounds, when all the players are there, and just get grounds passes (online, when ticket sales open) rather than an expensive package with prime stadium seating. Then we wander the outer courts and non-reserved stadium and find matches we want to watch. We can also watch practice, which is the only way we have seen Roger in person ( at Melbourne).
The main matches with the big name players will be shown on screens around the grounds and offer a better view of the play than a seat high up in the stadium.
I will say the French Open was our least favorite of the tournaments we have attended. The security screening to get in is serious and time-consuming ( more than an hour in lines). And they admit too many people into the grounds. It ends up very crowded and difficult to move around. But the energy is great and it is fun to be there.