It's funny, Chicago has a vibrant lbgt scene and also has a suburb called Aurora
... so initially I responded Chicago, but then I noticed it was Dallas. My bad.
Seattle has decent public transport in the city and if you plan it right you can get around in Everett. Everett is much more car dependent than Seattle. There are bus lines going between the cities and if you get up early enough in the morning there's a bus line with I think 6 runs in the morning, and 6 return times in the afternoon. That's the killer ... if you work at Boeing, or want to go from Seattle to Everett in the morning, you have to get up at the crack of dawn or earlier.
Within Seattle though, it is no problem whatsoever.
Seattle has a vibrant lbgt scene and the area is very accepting of that lifestyle. It's very "don't care" more than anything else really. I have yet to experience homophobia or xenophobia of any sort out here.
Denver, too, is very accepting, but its suburbs are another story, or so I've heard.