I can't really be certain about the crowds, but a little basic logic tells me that if it's colder, then there should be lesser people than there would perhaps be in the summer months, however, this is just me having a bit of a guess.
For your day at the Walt Disney Studios Park, some of the better attractions include Twighlight Zone Tower of Terror, Crush's Coaster and Ratatouille: The Adventure. Some of the other attractions worth taking note of are Rock and Rollercoaster, all the Toy Story Playland attractions and Mickey and the Magician live show in the Animagique Theatre. It's worth nothing that as this is such a small park, lines for even the more tame attractions can get unbelievably long, such as Crush's Coaster. Also, during your visit, Season of the Force will be happening at this park, which depending on how late you stay, concludes each night with a nighttime projection show on the Tower of Terror called "Star Wars: A Galactic Celebration". As well as this, the Season of the Force even also included other limited time entertainment which you should be able to find out more info on the website or on a brochure in park.
At Disneyland Park, the main attractions include Hyperspace Mountain, Big Thunder Mountain, Pirates of the Caribbean, Star Tours: The Adventures Continue, Indiana Jones et le Tempil du Peril and "it's a small world". A tip for getting some extra rides on these more popular attractions would be to sacrifice the time when most people would be viewing the parade as lines for these ride should be much shorted then. During your trip, there are also a number of rides under renovation including Phantom Manor and a number of the Fantasyland rides. Here is a link to see all scheduled renovations at Disneyland Paris: http://holidays.disneylandparis.co.uk/eep.html
And finally about you staying onsite, in the mornings there is Extra Magic Time, which you can find out more on this link: http://www.disneylandparis.co.uk/faq/park-hours-schedules/extra-magic-hours/
. The dates that you are visiting the resort, Extra Magic Time runs from 8:30am to 9:30am in both parks.
I hope this post helps a little so that you can experience as much as you can at the resort. Each park will have an up to date brochure available at the park entrance with the all most current info on show and parade times at the parks.