I have been here twice, once when i was really young and the second time was just last summer. The place got a few new roller coasters since the last time, but I had just as much fun as I did as a kid. Le Monstre is, I believe, the biggest wooden roller coaster in North America! We went on almost all the roller coaster and le Monstre was our favourite.
If you want to go for a day at La Ronde, you want to get there really early, before the doors open and rush in when it does. You should get the tickets online before hand so your not in line to get them as others get in. The wait time for each roller coaster gets longer and longer as the day goes, so be prepared for the wait.
Food is the same at any amusement park, expensive junk food. But I guess its part of the experience.
Next time I am in Montreal, I am definitely going back!