Thanks everyone for your replies - they're all so helpful!
Krafts - yes, we are in for a treat. Alaska has been on our "to do" list for sometime, but for one reason or another we've never made it. This year, we're not letting anything stop us.
White Pass is definitely on our plans for Skagway.
Juneau is the destination where it seems like there are far too many options to choose from. It'll be hard to make a final choice on what to do there - but, as we've been telling each other, it just means we'll have to go back again!
Now, we just have to choose which cruise to take.
Anyone have any pros/cons from personal experience for Princess, Holland America, Carnival, Norwegian or Celebrity?
We like the Freestyle idea of Norwegian and that it's very casual. We're both casual by nature and, especially on vacation, we like to limit dress-up occasions. The only problem is the Norwegian itinerary seems to have shorter stays in port - leaving mid-day on all of them which is a bit of a turn off.
We don't really care what the average age of travelers on the ship is and we're not into casinos and shows, etc. So, the things that matter to us are: comfortable beds, decent/clean room, good food, casual atmosphere, etc.