There really is a lot for non-pilots to see and do in the Portland metroplex, too much to list here, and pretty much anything you can find in any other big American city. But September is usually harvest time and there are lots of farmer's markets, wine tasting tours, and similar outdoors events in the region west and southwest of Portland this time of year.
There is a large mall of outlet stores on I-5 in Woodburn, which is only about 30 miles from McMinnville. You can go to the Oregon coast with nothing in particular to do except to enjoy the beauty of it. Either up to Tillamook or down to Lincoln City, equally nice. There is the Spirit Mountain casino in Grand Ronde, which is on the way from McMinnville to Lincoln City. If you're feeling outdoorsy, you can also plan on staying at the Flying M Ranch near Yamhill, which is only about 30 miles from McMinnville. They have a 1000 x 40 turf strip at the ranch (look up OR05 on AirNav), not likely to be doable in a KR, but it is a nice place to stay, ride horses, eat, or whatever. If you fly over to the coast, be cautioned that it is sometimes very windy and landings can be a bit tricky when the winds are up. Winds at the Cape Blanco lighthouse, the westernmost point in the lower 48, have been clocked at 184 MPH ;o) Oscar Zuniga Medford, OR