Downtown seattle for sure, or eastside is nice as well (downtown bellevue). Like hook mentioned above, I would still recommend a car, maybe one or two of the days just so you can go places freely. I've honestly only been on the public transit in the greater seattle area once or twice and its not as easy as NYC or even NJ transportation.
What kind of food are you interested in? There are tons of great restaurants in downtown from sushi to steak and everything in between. If you're a fan of seafood you'll be in for a treat.