Are there toilets on Rer trains between CDG airport and Paris centre? Also the train from Paris to disney land?
No the RER B trains from CDG to Paris no longer have toilets on board. This changed at the end of 2011 and any remaining train cars with toilets have been permanently locked due to inability to keep them clean and to prevent security issues.
Same with RER A trains from Paris to Disneyland, no toilets.