Well, I am Canadian. I live in Edmonton Alberta now, however, I grew up in Vancouver B.C.. I would strongly suggest that they take the Disney Cruise from Vancouver. They should at least spend two days exploring the wonders of Vancouver before setting out on the most scenic breathtaking view they will ever experience in a thousand lifetimes.
The children on a Disney cruise are pampered with activities that are tailored to their favorite characters and imaginations. I've had a friend take a Disney Cruise with kids a little older and the young ones still speak about the adventure and the activities they experienced. As for the adults, yes, the price is higher, but well worth it considering the demographics of this trip as opposed to other lines. My Son went to Alaska on Celebrity and at 25 was the young boy with the pretty wife. My sister and brother-in-law went when they were in their 50's on Norwegian once and they did not enjoy as the crowd was quite a bit younger.
I have been there for business and sailed as a young cadet on a Canadian Minesweeper through the passage. We will go there in a few years ourselves on a cruise.
So you put a check mark from me for Disney to Alaska.