I realize that Tom Douglas may be as big of a tourist attraction as the Space Needle but I can't help it, I think he's a fine chef. I echo Suzanne's post about going to a restaurant that isn't pretending to be something it's not. Etta's is totally relaxed (but what place in Seattle really isn't) and the food is good. Sit back & relax! It's in a good location for you to take a walking tour of the market, head down to the pier, or just browse around downtown.
On that note, if you will have already hit the tourist traps or your friends have been to our fine city before, I vote for Salty's in West Seattle or Ray's Boathouse. I think everyone already knows my opinion about the view of the downtown skyline from Salty's, as mentioned in my previous posts about said subject. And Ray's, well, it's just darned good food!
Have fun and two thumbs up to the grandfolks for taking the tater tots off your hands for an evening!