We did Norway on QE2 last year. Trondheim we took the bus to the Cathedral and joined one of the english language tours of the Cathedral and the Archbishop's palace. Both excellent value. Tickets can be baught at the tourist office by the Cathedral.
In Bergen we took the bus into town and the funicular railway to the top of Mt Floyen and walked down through the woods. Then did the Fantoft Stave church and Grieg's house.
At Hellesylt we did the overland to Geiranger, a trip that still makes me draw gasp at some of the views. Truly beautiful.
Stavanger we cruised the Lysefjord which was wonderful, we stop off for pancakes and coffee on the way back and go seal spotting. Later we wandered around the town.
I don't know about the other places, but there is a lot to be gained by taking a short excursion and then walking round the town, if it's big enough to walk around of course.
We enjoyed all our trips.
Hope you enjoy yours, the scenery's just wonderful.