We went to Paris last year and did a 1-day trip to DLP for our first visit. We bought our tickets from 365TicketsUSA website, and the Mini (low season) 1-day/2-park tickets were about $65 each. I was skeptical at first, but they worked perfectly.
Try to get do the Ratatouille ride first and explore that area of WDSP, walk through Toy Story Playland, see Cinemagique (post Happy Hour worked fine for us). I did ride their Tower of Terror since it was a short wait. The 30+ minute wait for Crush's Coaster didn't seem to move, so I got out of that line.
In DLP, ride Phantom Manor, Big Thunder (it's different because it's on an island, so there's a long tunnel at the beginning/end of the ride), PotC, Space Mountain 2, explore Main Street Arcades, Dragon's Lair under the Castle, Alice's Labyrinth, Pinocchio's Voyage.
We also found a Happy Hour spot in bar of King Ludwig's Castle restaurant in the Disney Village. Perfect way to rest for a bit after some rides but then go back in the parks for evening shows.