If you're up for going into the city, the MAX train is great fun and would give you a break from all that driving (
http://trimet.org/max/stations/index.htm). You can get an all day pass, with unlimited on/off, for <$5. The train makes stops at or near:
Rose Garden Arena, where the Trailblazers play;
Saturday Market, which is also open Sundays (
http://www.portlandsaturdaymarket.com/);
Chinatown, with many restaurants and the Chinese Garden (
http://www.portlandchinesegarden.org/);
Pioneer Square, the main downtown mall area, where Macy's Christmas lights are already going up;
Oregon Zoo (
http://www.oregonzoo.org/), Forestry Center (
http://www.worldforestry.org/) and Children's Museum (they all share a parking lot).
If you find that you're exhausted, there are some beautiful walking paths along the river just east of the Red Lion. Restaurants include Joe's Crab Shack (a national chain, but a fun place to eat nonetheless
http://www.joescrabshack.com/), Who Song and Larry's (Mexican), McMenamin's (a small, local brewpub chain with a laid-back atmosphere
http://www.mcmenamins.com/index.php?loc=33&category=Location Homepage), and Beaches (My IL's favorite, both for the fun, friendly atmosphere and good eats
http://www.beachesrestaurantandbar.com/).
HTH!
ETA: Whoops! I should check my dates before I post--you're probably back already--hope you had fun! And maybe my looooong diatribe will help someone else <grin>.