I would definitely stop at Exit Glacier in Seward.
Once in Anchorage, drive a little ways north and hike the Thunderbird Falls trail and drive up to Eklutna Lake (better than Mirror Lake, IMO) and rent a kayak.
Denali is a must but don't get your hopes up on seeing the actual mountain. Weather conditions have to be right. On a clear and sunny day in Anchorage, stop by the Sheraton Hotel and ask for access to the Summit room on the top floor for some killer views of Mt McKinley and Mt. Foraker. You can also see them from the concierge lounge at the Marriott downtown.