I don't live in Portland, but I've been down there and it's a fun place to visit.
I'd stay downtown because you can walk to everything. The Hilton and the Marriott are close to Niketown, and the Columbia Sportswear Store, not to mention McCormick and Schmicks Steakhouse for a snack. Walk the Riverfront to China Town and ride the Trolley back.
Pioneer Place for more shopping. (Williams Sonoma, Sur La Table, and Pottery Barn.) The Pearl District has great places for drinks and appetizers! It also has neat galleries. And more shopping for Home Decorating. (Your wife's gonna have a blast!!)
Don't forget to make sure the Hummer will fit in the parking garage, or leave it with the valet so everyone can admire it!
I forgot the guy things. I do have friends that provide Guide Services for salmon/sturgeon fishing. That's a must, if you like it. The spring Salmon will be in by then and they can pick you up at Waterfront Park/ walking distance.
Lastly, reserve a day for a Hummer Gathering!
P.S. If you leave in the afternoon, spend the first night at the Columbia River George Hotel in Hood River, OR. Very romantic.
OKay. There's the shopping agenda. Have Fun!
PM me if you need more!