I have a conference in Versailles early June and it is VERY light duty from a work standpoint - plenty of time to ride if i choose. I'd love to be able to ride from CDG as I have the time to and can meet all my biz responsibilities. Any advice on how doable this is? I don't want take on a ton of headaches with this adventure. Would be riding from CDG to Versailles and staying there a couple of days, then to Paris for a couple of days, then back to CDG for the trip home to the US.
If you look on a map, you'll see that CDG (Charles de Gaulle airport) is northeast of Paris, whereas Versailles is southwest. I don't think there is a good way to ride from CDG to Versailles. I would recommend that you take the RER from the airport to Versailles. (If you happen to be arriving on a weekend, then you might consider riding.) You can take your bike on RER trains except for rushhour Mon-Fri. All day on weekends is OK. You'll need to transfer at St. Michel.
You will find much nicer places to ride if you start from Versailles. If you've got time for a longer ride, bike to Chartres. For a shorter ride, the Rambouillet forest.
If there's a rideable route, you can find it with this website: www.viamichelin.com . Use the cycling option. I'm not saying that this is a good idea, just that viamichelin can find you a cyclable route. From what I remember (it was a long time ago), central Paris isn't a bad place to ride a bike, but CDG didn't look too bike friendly.
Google Earth would be a good way to check out your route ahead of time.