Is there any reason why you want to prebook? Usually there are 2-3 taxis waiting at the official stands at CDG, and more will be called up as needed. Some are larger, some are mini van types.

You can preorder a Maxi cab, or a 'Family cab' on the G7 site which takes up to 7 passengers and has child seats http://www.taxisg7.fr/decouvrez-nos-...ille-familycab If the address is an issue I would just call them if you really feel it is necessary to prebook.

Remember too that there is a surcharge for extra pieces of luggage.

I did recently take a minivan shuttle service to CDG instead of my usual taxi; for some reason my doorman offered me one which was a flat fee. I'm not sure why after all those times he volunteered that service but I suspect that it was a 'friend' Service was fine, but I didn't need the large vehicle and missed the personal chat I usually have with the taxi driver. There are a lot of shuttle services with poor service records so you may want to look into the G7 option.