About the only place in the Wasilla area that I'd recommend for food is the Motherlode Lodge up at the base of Hatcher Pass, on Fishhook Road. Other than that, there's not much in Wasilla other than the Iditarod headquarters, and I won't lie to you: that town is my least favorite place in Alaska.
Downtown Anchorage has plenty of good restaurants (Glacier Brewhouse, Orso, Simon & Seaforts, Humpys, Snow Goose, Sacks, Fletchers, Corsair, Crow's Nest, etc.).
You'll enjoy Seward, but be warned that it will be packed for the 4th of July.