I need to get from CDG to Disneyland Paris. What's the best way rather than taking the RER?
There are direct TGV trains which go direct to Cinderellas Castle. There are typically trains every 15 minutes or so. BTW, the official name is Disneyland Paris.
Trains don't run as frequently as Michael suggests. Here are some departure times for the ten-minute ride to Marne La Vallee Chessy (the Disneyland station): 08:21, 08:57, 09:25, 10:27, 11:42, and 12:58. The walk-up fare varies between €16.60 and €25.
VEA shuttle buses run every 20 minutes during peak hours.
Take the Direct Experss bus to Disney. It picks you up right out front of the terminal and takes you directly to your hotel. For limited mobility this would be the best way to go IMHO. French train stations are not always easy for people with mobility issues. This way also means you will have help with luggage.
From thier webpage
http://visit.disneylandparis.co.uk/how-to-get-there/index.xhtml#contentj