Where's the best place to buy tickets?
you can try online at DLRP's website, or pop up at the parks ticket booths if you have time to spare. But I don't know about local resellers, depending on where you'll be when you book the tickets.
Anyway, DO NOT EVER trust those who might try to sell you tickets on the Esplanade at the entrance of the parks (just before security check). And be cautious about sites or people promising huge discounts. Always go for authorised resellers.
Any particular day better to go than others, we were thinking Mon and Tues since more sites are closed in Paris those days?
tuesday is a good bet. Weekends are crowded, Wednesdays too, since many kids don't go to school.
thursday might also be slow, but it all depends when you go, especially if France and Spain are on holiday
here's a link to a PDF file with all european school holidays :
http://eacea.ec.europa.eu/education/eurydice/documents/calendars/school_calendar_EN.pdf
Does DLP have fast pass like DW?
yes, some attractions/rides do have them.
Tower of terror, Big thunder mountain, buzz lightyear laser blast, star tours, indiana jones, space mountain, peter pan's flight are among those (only from memory)
Should we take the train in or drive, i'm worried about the safety of the trains at night.
Driving in Paris is sometimes a nightmare. Especially at rush hours.
Driving to the parks might sound a good idea if you avoid those rush hours. But you'll need to budget €15 each day for the park's parking lot, since you're staying offsite.
Taking the train to the parks will also be quite time consuming. the ride is roughly 45 minutes each way, so consider 1hr including wait times at the station. Train safety at night is a relative thing. They're usually safe, but, you know, somtimes you're in the wrong place at the wrong time. Anyway, many guests do take a train back home.
I know I'm not helping here, but the "should I drive" question is always a tough one. What do you prefer ? Can you imagine driving home for maybe one hour after a day at the park ? Do you have a private parking spot at your appartment, because parking in paris is like fighting a war. you may not find a spot when you come back.
How far is your hotel/appartment from the subway/train station, will you need to make connections, how long will it take ?
that's something I can't really help you with.
My choice would be to drive, no matter what.
The other thing you have to factor is the kids' comfort after a day at the park. depending on when you exit the parks, you might end up on a train packed with people, and kids unable to even sit or rest. The car offers much more comfort and the opportunity to sleep for the younger ones.
yes, one advice : enjoy yourself
If you're ever to take your car into paris, pay very close attention to where you park your car. Park in the wrong spot and your car will be impounded faster than light.
