First question: what is important to see.
Second question: Your own itinerary - adjustable, or a fixed tour...
With those questions clear in your mind, you can limit your efforts to the type of trip you want. There is way more to see here than you will have time for.
Anchorage is a BIG city. Great for aviation, and things to do close, but it is A CITY. If coming to see Alaska, run far and fast from there. The Park's highway, trains, ships, bus tours all offer seeing stuff on their schedule, but you are in a crowd. I don't like crowds. Yes, you meet great people from other parts of the world/country, but if coming to meet Alaskans, and not be hearded like an Oklahoma sheep, you might want to think about doing it on your own, rental car or RV.
The big rainforest is along the coast up into the Keni Peninsula. Tundra stuff is over most of the interior, wildlife is all over, just learn to drive early in the mornings, (as in 4 am or dawn) and be watching late in the evenings.
For me personally, I don't like the tourist crowds. If you can get a permit to drive to Kantishna, do it!!!!! But otherwise, if the weather is not good, the Denali Park is another hotel full of non-Alaskans. Your time might be better spent walking around outside of Healy, Talkeetna or just hiking up a side road anywhere without a crowd.
I do not know how much time you have, but Beluga Point just south of Anchorage, (before Girdwood) is a great spot to pull over and see Dall Sheep and Beluga Whales. (bring good binoculars and a spotting scope if you have one). If you decide to continue south to the Keni, consider traveling very early in the morning, and stay off of that road friday afternoon (southbound) and sunday afternoon (northbound) for traffic reasons... ask DaleC about that one!
Wittier has a tour to the Fjords and glaciers... take it if you can handle the boat and are there. We have glaciers here in southeast also, it is something you should see while here. Seward also has tours to the areas Wittier does.
Fairbanks has a gold dredge (Ester actually), as does Dawson YT. Both are left over from the gold days. My grandfather worked the one in Ester, his last trip up there he saw names of friends still in the tables at the Malemute Saloon there... tourist stop, but historic.
The pump house in Fairbanks has good food, was the actual pump house supplying water to the dredge nozzles.
My friends have a new B&B about 100 miles south of Fairbanks if you want the info let me know.
Circling through Delta and down the Glen Highway past the Matanuska Glacier is a nice drive... there is a little chinese place right after the turn south in Delta that is excellent.
So much land to see...
If you are going to drive on your own, head to the nearest book store, ASAP, and buy a MILEPOST. Simply, it is the bible for road travel in Alaska.