What's your budget? How long will you be there? What ages children?
Staying in a Disney hotel has one big advantage - Extra Magic Hours. If you want to see Anna and Elsa in the Princess Pavilion that's about the best option. Sequoia Lodge and Santa Fe are fine, both walkable distance to the park. Slightly cheaper option is to go for the associate hotels - Kyriad, Explorers, Dream Castle, Circus. A free shuttle bus will take you to and from the park.
Trip Advisor has a dedicated forum for DisneyLandParis, which is pretty active and up to date.
we went about 2 years ago - booked hotel and park tickets over the phone with Disney which meant we psid a deposit rather than the full amount We booked Eurostar separately. we stayed in the Santa Fe which was fine for us - I think most bedrooms have 2 double beds for a family of 4, so you may want to take this into account depending on the dynamics of your family.
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