Here is a list of all of the CDG to DLP options:

1. TGV

(non refundable fares vary depending upon departure time from 15€ to 30€)

Travel time 9-10 minutes

http://www.voyages-sncf.com/

depart: AEROPORT CDG 2 TGV (95) arrive: MARNE LA VALLEE CHESSY

2. Bus (VEA)

http://www.vea.fr/uk/index.asp

Adults – 17€, children under 12 – 13€

Departures every 20 minutes from 8:55 a.m. until 8:05 p.m. except:

Until 8:25 p.m. on Monday & Thursday

Plus 10:25 p.m. on Friday

Plus 9:55 p.m. on Sunday

Travel time about 1 hour

3. RER (train/métro)

http://www.ratp.com/

RER Line B towards Chatelet-Les Halles; change to Line A for Marne-La Vallee/Disneyland

This is probably the cheapest option (8.20€) but it can take up to 2 hours.

4. Shuttle

paris-blue-airport-shuttle.fr/index_en.php

Private shuttle from 1 to 8 people – 60€ to 100€

Shared ride from 1 to 8 people – 45€ to 12.50€ per person

http://www.paris-shuttle.com/

Hi copy from sastro, Hope he don´t mind

Mutter

the scnf site is very hard to follow (unless I am doing it wrong) to work out exact prices and times

I go the TGV from DLP to CDG a couple of years ago and it was very easy. I bought a ticket from the station at DLP and it was amazingly quick. You can get times via http://www.tgv.co.uk/

Amazingly, this question is asked every 3 to 4 days (sometimes even more often). One can only assume that the forum's search function is in perpetual disrepair or people actual prefer to pose a question and then wait to see what happens; somewhat like a fisherman waiting for tiny nibbles on his line.

So, no Mutter, Sarastro does not mind that you post his research, it's all in the name of helping others anyway.

Unfortunately, you left off item 5, a valuable and viable alternative in many situations:

5. Taxi

http://www.taxisg7.com/

Convenient but can be expensive

Travel time about 1 hour

Cost estimate: 75€+