What internet provider do I choose?

Comcast is typically one generation ahead of Qwest, mostly because of the medium (coax is newer than copper). My default is to go for cable, but it depends on your neighborhood. There is a third option, Clear, that just became available in our market too.
When choosing your interwebs, there are multiple variables. Cost and speed duke it out for primacy. Reliability and convenience run a distant second. Check both Comcast and Qwest to see how fast you can get. In older Portland neighborhoods, Qwest often sucks. In Beaverton, it is significantly faster. Once you get their assurance of x speed for x location, check the price. Both have rotating specials that will save you a ton of money.
Do NOT ever use their built in email. If you ever switch providers, you get the ugly. This way, once your special for X internet provider ends, you switch to Y.
Clear is a dark horse in this race. They are a new 4G wireless provider in the area, at about 4MBps (comparable with low-end cable or high-end DSL). It works like wifi with a 7 mile range. Portland was the second US market to get it, so the hardware you buy will only work in the metro area and, I think, D.C. or Virginia somewhere. It's certainly growing, but it will take several years to cover the country. It is optimal for someone who needs to do their computer work on the road, but in PDX.