Trip to Versailles

Take the RER C and get off at Versailles Rive Gauche/Chateau stop; it is a short walk from there. It is roughly 7 Euro or so round trip (you get two tickets so you don't have to mess with buying a ticket to come back). PLan to arrive at least half an hour before the chateau opens. And have your ticket (or museum pass) in advance. You still stand in that hideous long security line, but at least don't also have the ticket line) On Fountain days, you pay extra for the garden.
Here is our trip just to the garden last October; we felt like the fountains were worth it.
https://janettravels.wordpress.com/2016/02/15/fountains-of-versailles-a-little-chaos/
Some people suggest doing the Kings Apartment tour first thing in order to avoid the long security line. You can book on line for that. The issue is that if the fountains are not on all day, and it is hard to see the fountains and the kings apartment and the chateau not to speak of the rest of the estate.

Janettravels44 Is it difficult to navigate the Metro to get to the RER C? Our hotel is very close to Metro Station Cardinal Lemoine

On the contrary. It is dead easy to get to the C and in fact the best route avoids the center of Paris where the C has been under renovation from time to time. You just hop on the 10 metro at Cardinal Lemoine and ride it to Javel where you can get the RER C to Versailles Rive Gauche. The ticket Paris/Versailles Rive Gauche can be used from Cardinal Lemoine to Versailles Chateau/Rive Gauche.

Get two tickets of course so you have one for the return.

Hello
In a Paris now...went to Versailles yesterday. Yes RER c line train best option, to Versailles Rive Gauche, note there are 3 stations in Versailles, make sure your train goes to this station ....return also from this station. Probably have to decide whether fountain Display (11-12 or 3:30 - 5 at intervals) is important and plan your time. We booked Kings Aptt tour at 9, first tour and got in without much waiting. We were alone except for other people in this tour about 15. After with massive crowds to view remainder of Chatteau. Purchased Le Passport on line and additional tour ( 25€ + 7€ for tour). Go early...leaving Paris at 8 or so...many visitors , this place is huge! Worth seeing, good luck, have fun.

Janie, we have tickets for the 9:00 tour next month. Since, after the tour, it sounds like we will be joining the crowds to get throught the rest of the palace, will we be able to make the 11:00 Musical Fountain Show?

The 'Musical Fountain Show' just means that fountains are turned on and canned music is playing. There are a dozen or so fountains running and they are separated from each other by fences, hedges and woods. You get a map and then seek them out. Here was our visit in October:
https://janettravels.wordpress.com/2016/02/15/fountains-of-versailles-a-little-chaos/
We particularly liked the Ballroom Fountain and the Three Fountains and the Apollo at the foot of the gardens is a great photo op too. The fountains play for the period and then shut down and are turned on late in the afternoon. So you aren't exactly 'late for the show' -- you can wander off to whatever fountain you most want to see whenever during that time period. We missed the train we wanted and so didn't get there till 10:20; it just meant we had a little less time before the fountains shut down at 11. You can leave the gardens and go into the wider Estate (Grand Canal, Trianon, Hameau etc) and then return to the gardens for the 3:30 'show'. Just hang onto your garden ticket for re -entry.

Thanks, janettravels44. That is really helpful! Nice photos and write-up.