Respectable Hotel
Although not central it is the same distance to both the Needle and Westlake Center from the hotel. They are both in walking distance but if you aren't inclined than the hotel offers a shuttle service every hour to these two attractions plus the Convention Centre. 
The room wasn't particular modern but it was very clean, spacious and homely. There was a small kitchenette with a microwave, a desk and couch/tv area. Very comfortable.
The staff were excellent. Well informed and friendly.
The biggest let down was the breakfast. There was no real food. The eggs were powered, the waffles tasted of bitter chemicals from the spray you needed to use on the waffle maker. No real milk and powered tang instead of orange juice. The apples were rotten on the inside even though they looked perfect on the outside. The bananas were under ripe and crunchy even though again they were perfect on the outside. Go to Wholefoods instead for your meals which is on the way back to Westlake Center.
The cheapest way to and from the airport is definitely the train. It's only $2.50 per person to Westlake Center. From there a taxi is only $5-6 or a 5-7 min walk. After checking out book the free shuttle to take you back to Westlake Center train station.