If you stay in Paris you can get a combined day ticket and train ticket. That lets you into 1 park for hte day and the other after about 5pm. With a 2yr old I would leave the studios until the evening.
If you are going for the first time I would stay in Disney. Sequioa Lodge is good, Newport, lovely, they say the best thing about the NewYork style one is the veiw of Newport, and the mexican one never seems to get good reveiws.
Going by Euro star is fine but timetables can be a little confusing for the RER, the trains have a four letter name and you have to fgger out what name you are looking for its all on big boards along with a map in the stations, don't panic if you miss atrain while checking this thay are very frequent and better than going on the wrong train.
If driving you go right round Paris past GDG airport and miss out the centre.
We flew in to Beauvais with Ryan air and hired a car, the second time when we stayed in Paris we took the bus from Beauvais in to Paris (takes ages), no train station and quite far out from Paris. Note that the Disney buses don't serve Beauvais. We have flew into CDG and the shuttle bus was great.
Food in DLP is pretty rubbish, during the summer you can at least sit outside. They can't do fast food, they try but they can't, its slow and cold.
Buffet style and self service seem best as you will wait forever for service. Ok if with partner to keep seats and amuse children rather than trying to find seat with tray in hand.
Tip for cheaper soft drinks and snacks pop in to the train station positioned between hotels and entrance, has a kiosk and vending machines. Also there is alegedly a petrol station bhind one of the hotels but never tried that.
With regards to speaking french do try a little it is appreciated, I never learned Frech at school but picked up enough to buy tickets and order food in Paris.