I wanted to wait until I got to Paris to buy a train ticket to Bordeaux. Wanted to take a slower commuter train, not high speed. Is is okay to buy the ticket when I get to the CDG airport instead of online ahead. Is there any chance all seats would be sold out? Do they accept senior discounts based on ID instead of buying a Senior travel pass for 75 euros each? Thanks for any help.
Senior discount, if not sold out and if traveling outside rush hour= 25%. With the card, 50%.
I'm not sure what your purpose is here, but if you just want a nice train ride I strongly recommend the regular high-speed train. The slow trains out of Paris take from 13 to 18 hours and entail multiple transfers. That's not an adventure, it's an ordeal! Since you are already at deGaulle I'd look into flying. However, there are several direct trains from the airport that will do the trip in 4-1/2 hours. This is a very comfortable ride.
train from paris to Bordeaux doesn't pass by many interesting sites. if you really want a good ride, and can do a little bit of driving, then i'd suggest you rent a car in Bordeaux to drive around to see some small villages or even drive to salart on the country road. low speed, pass by many interesting villages, great view, and very easy drive. you don't want to sit on a slow train from paris to Bordeaux - it's not short distance and my last ride took about half day.