I worked in Portland for a while, and really enjoyed driving the area. You can leave town and drive to the ocean and see expansive beaches, with forests along the way. You can leave town and go the other way and loop around Mount Hood, then drive along the Columbia. It's pretty at any time of year, although the road to Mount Hood may be snowed out during the winter. A good "hen" experience. Wineries, orchards, lots of touristy stuff. When the tide's out, the long walks on the beaches are magnificent, especially around sundown. Either direction makes a nice day trip.
From Portland, it's not a terribly long drive to Seattle. When in Seattle, try to do the following as time allows:
Go to the aquarium. It's worth it just to see the giant octopus.
Take your car on a ferry and then drive along puget sound out to the beaches at the indian reservation. Seaside towns are along the way, tidepools, etc. On the way back wander around through some Olympic rain forest.
China town for dinner and wandering around. If the tea shop is still there, stop by. Your wife will like it. There is a beautiful selection of tea services and many delicious teas.
Pike street market for the spectacle of it
Try some good seafood at one of the restaurants near the aquarium.
Try not to trip over too many bums when you're near the aquarium ;-)
You'll both like it the area.