Laurie - last September I flew into Seattle with my family and we drove to Vancouver. It's not a long drive - 4 hours, depending on traffic. It's not necessarily and easy one. The airport on on the south side of the city, so you need to drive through the city to get north. Traffic can be a bear. I'm not sure how the border crossing is there lately. I know yesterday in Detroit I waited about a half hour to cross, in the middle of the morning (10:30). Rental cars are definitely permitted across the border.
Let me know if I can help further.
"Is ice hockey hard? I don't know, you tell me. We need to have the strength and power of a football player, the stamina of a marathon runner and the concentration of a brain surgeon. But, we need to put all this together while moving at high speeds on a cold and slippery surface while 5 other guys use clubs to try and kill us. Oh, yeah, did I mention that this whole time we're standing on blades 1/8 of an inch thick. Is ice hockey hard? I don't know, you tell me. Next question."